G-8945 TRANSFER-TRIP SYSTEM

Transcription

1 T om or r ow 's T el em et r y T od a y! Da-Tel Research Company, Inc. Phone: (970) N. Park Avenue / P. O. Box 1206 Fax: (970) Montrose, Colorado info@da-telresearch.com G-8945 TRANSFER-TRIP SYSTEM FREQUENCY PROGRAMMABLE CRYSTAL STABILIZED TRANSMITTER IEEE STANDARD DUAL TONE, DUAL SHIFT PROTECTION OPERATING TIMES OF LESS THAN 1 CYCLE REDUNDANT LOGIC IN-BAND SIGNAL-TO-NOISE DETECTION ISOLATED INPUT/OUTPUT POINTS INDUSTRY ACCEPTED DESIGN FLASH KEYING PROVEN DEPENDABILITY AND SECURITY FREQUENCY AND AMPLITUDE STABILITY IN-SERVICE DIAGNOSTICS AND VISUAL INDICATIONS MODULAR CONVENIENCE 4/02 PAGE 1

2 DESCRIPTION The G-8945 Transfer-Trip System provides secure, economical and reliable protective relaying. The circuit simplicity of the G-8945 defines a new industry standard with no loss of features. Installation of the G requires only a screwdriver. The G-9055B TT Transmitter provides standard IEEE dual tone shifts and inputs. The signaling is the shift-up, shift-down method of using guard and trip frequencies. Secure opto-isolators protect the input from high noise conditions and provide isolation of transients from the transmit input. The transmitter is crystal stabilized and operates over the 300 to 3500 Hz range. To support field tests the G-9046A DTT diagnostic module is available. It provides for manual test keying of each channel and external notification when in the test mode. Protected communication inputs meet or exceed IEEE standards. Both the send and receive ports are equipped with high-pass filtering. This filtering attenuates 60 Hz and harmonics below 600 Hz which can be induced onto the line during a system disturbance. Packaging options include standard 19" relay rack mounting as well as specialized mounting. All wiring connections are made using screw terminals at the rear of the shelf. These terminals have the capacity for up to #16 AWG wire. The typical receive station employs two receivers, a logic module and relay modules. Relay modules are chosen based on specific output contact requirements. Relay contact ratings and operation times for the different relay modules are detailed on page 8 of this brochure. Optionally the terminal status and signal levels can be monitored with a G-9125A Level or Status Display Module. Ten latched targets and 4 level channels are monitored to indicate and provide external alarm. The G-9056 TT Receiver features a scaling amplifier followed by an automatic gain amplifier to drive the discriminator. When all internal gains are set, the only field adjustment needed is the setting of the scaling amplifier. Four of the G-9056's circuits monitor signal parameters. Those signals include low level, high noise, signal-to-noise ratio, and modulation failure. Each, when enabled, will block the G-8033E Logic Module to prevent a false trip output. The G-8033E Logic Module provides the timing checks and logic of the G-8945 Transfer-Trip System. The guard-trip signal must arrive within an adjustable timing window of a maximum of 100 ms. This window is set at the factory for 20 ms. A trip-persist timer insures that the trip signal, once received, persists continuously for an adjustable 1 to 10 ms, factory set for 3 ms. The logic module brings these timing tests together with the errors from the G-9056 TT Receiver to drive the trip output. A less secure, permissive output driver is also available. FEATURES DUAL SHIFT-ON-TRIP COMMAND The G-8945 is designed around the dual tone channel concept where one channel is shifted up in frequency and the other channel is shifted down. Both channels can be independently or simultaneously keyed so that permissive or direct tripping schemes are supported. This dual tone configuration insures that single alien tones and/or tone translation do not cause the assertion of false trip commands. OPERATING TIME The operating time of the G-8945 is 1 cycle or less, exclusive of the transmission channel delay time. This time is measured from the application of the keying signal to the output at the receive shelf. The delay time is dependent on the channel bandwidth chosen and the output relay's response. Included in this time is the recommended trip persist check of 3 ms. SECURITY AND DEPENDABILITY Security and dependability, the hallmarks of transfer-trip system design, are incorporated in the G-8945 Transfer-Trip System through the following important features. Dual FS channel configuration allows only one of nine normal states to assert a valid trip command. Narrow bandwidth channels and a 180 degree shifting discriminator reject both out-of-band and in-band noise. High speed in-band signal-to-noise detection without extended trip times or additional modules allows operation if the signal-to-noise ratio has not degraded below the threshold level within the channel's bandwidth. Logic and timing checks on both channels must agree at the receiving station. Redundant logic and timing tests are optional. Signal levels, signal frequency, frequency stability, signal-to-noise ratio, individual channel sequence timing checks, and adjacent channel timing checks must all prove valid before a trip command is asserted ensuring security and dependability. SUPPLY VOLTAGE The G-7800C DC-DC Power Supplies are designed using saturable core reactors for ruggedness, stability and metallic isolation from the station battery. The overall system will function with a source variation of +/-20% with power derived from any nominal station battery potential. A 120/220 Vac supply is available with an optional backup battery pack. PAGE 2

3 KEYING INPUTS The G-8953 Universal Input/Output Module optically isolates keying input circuits to provide security from destructive transients. Testing to meet or exceed both the IEEE SWC slow and fast transient tests ensures the reliability of each system manufactured. Each of the direct and permissive inputs allows field selection of the station battery potential used for keyng. The input keying circuits are designed with a threshold keying voltage which must be exceeded to activate the optical isolator, thus protecting against false keying due to background noise. AUDIO SIGNAL PORTS Connection of the shelf to a communication medium, 2-wire or 4-wire, is also protected by the G-8953 against destructive electrical transients that are induced onto these lines. The two audio ports are equipped with 60 Hz rejection filters. This prevents induced 60 Hz noise from causing the input's protective circuitry to clamp unnecessarily, thereby squelching the tones. Alternately the G-9300 Fiber Optic Modem module provides a direct interface for the audio tones to fiber. A fiber optic based G-8945 system allows the engineer to sidestep all associated GPR problems found at substations. Due to the inherent quality of the communications over fiber the security and dependability increase exponentially. ALARM FUNCTIONS Optional alarm points are provided internally and can be brought to the shelf's rear terminal blocks for external alarm. Consideration should be given to whether these points are to be form A or form C contacts and whether they are to be rated to meet SWC testing. Specify your contact requirements when ordering. PAGE 3

4 PRINCIPLES OF OPERATION G-9055B TRANSFER-TRIP TRANSMITTER PROGRAMMABLE Guard and trip channel frequencies are field programmable without additional programming equipment. All that is required is jumper placement according to the tables listed on page 19. There are no channel or bandwidth limitations within the audio frequency range. FLASH KEYING The G-9055B Transfer-Trip Transmitter provides flash keying. This field selectable feature repetitively sends the guard-trip signaling sequence to ensure receipt of the trip command. The flash keying sequence for the two transmitters is synchronized and inverted, one from the other. This is required because of the shift-up, shift-down format of the system. FREQUENCY AND AMPLITUDE STABILITY The G-9055B uses a crystal stabilized oscillator to generate the tones. Channel inter-modulation is reduced along with channel delay caused by the transmitter. High speed coherent keying circuitry saves approximately 1 millisecond compared to typical FSK systems. IN-SERVICE DIAGNOSTICS A full array of diagnostic front panel LEDs gives your technician the G-9055B's current status. For each of the two transmitters, the following points are indicated; present keying (trip or guard), permissive trip sent and transfer-trip sent. The transfer-trip sent indicator is a latched target LED with an acknowledge button. Front panel access to the level control pot allows in-service adjustment. G-9056 TRANSFER-TRIP RECEIVER SENSITIVITY The G-9056 TT Receiver has a dynamic operating range of +/-7 db from the nominal level. The initial scaling operational amplifier sets the module level at -30 dbm from the line level (nominal) within the range of -5 to -35 dbm. Once this initial adjustment is made, all other security settings are per factory specifications. The AGC amplifier keeps the tone level driving the discriminator circuitry stable for secure performance. The discriminator is a patented single coil, 180 degree shifting circuit which has proven to be less noise sensitive than typical discriminators. SELECTIVITY The four coil Cauer bandpass filter typically rejects the adjacent channel's mark or space frequencies by a minimum of 40 db. The filter notches are located at this minimum. Frequencies beyond those points experience an attenuation that decreases approximately 4 db, then increases beyond the 40 db measurement. LC filter design provides the extra level of component dependability required in a harsh environment. SIGNAL LEVEL PROTECTION The G-9056 TT Receivers are each equipped with low level detection, pre-low level alarm, high noise detection, and in-band signal-to-noise detection. The alarm thresholds for low level, high noise and signal-to-noise are continuously adjustable over the input sensitivity range. The pre-low level alarm provides early warning of a degrading signal level condition. The alarm threshold is approximately 2 db above the blocking level. Ter- db CHANNEL BANDPASS FILTER LINE LEVEL -5 TO -35 dbm FILTER RESPONSE NARROW BAND FILTER PASSES ONLY FREQUENCY SPECTRUM OF CHANNEL REJECTING ADJACENT TONES AND NOISE BY 36 db. LOCAL SCALING AMPLIFIER SCALING AMP SET FOR NOMINAL -30 dbm AT TP1. FIELD ADJUST BY DEPRESSING THE FRONT PANEL 'CAL' BUTTON AND ADJUSTING GAIN SO THAT 'LL' LED JUST TURNS OFF. ALL INTERNAL THRESHOLDS ARE REFERENCED TO TP1 AND NEED NO FURTHER ADJUSTMENT. TP1 AUTOMATIC GAIN AMPLIFIER HIGH NOISE THRESHOLD SET LOW LEVEL THRESHOLD SET S/N RATIO THRESHOLD SET DISCRIMINATOR OUTPUT DRIVERS, GUARD & TRIP MODULATION FAIL LOGIC ERROR T G BUS TO G-8033E FSK SIGNAL PROCESSING PAGE 4

5 minal dependability is 99% for carrier levels down to the LL threshold. FREQUENCY TRANSLATION Frequency translation is perceived by each G-9056 using the modulation fail detection circuitry. This detector indicates rapid translation swings typical to microwave failures. When a failed condition is detected, the G-8033E is blocked to prevent a false output. The shift-up, shift-down dual channel configuration will block tripping due to a gradual or steady translation of the channel frequencies. G-8033E LOGIC MODULE TRIP BLOCKING The trip-block input to the G-8033E comes from the G-9056 receivers. The G-8033E Logic Module supports trip-block intervals of 0 or 1 to 50 ms, adjustable for rapid return to operation once the block clears. DUAL CHANNEL TRIP SEQUENCE The G-8033E Logic Module combines the output of the two channels to generate the trip command. The guard-to-trip timing is checked for each channel. Upon loss of the guard tone, the trip tone must arrive before an adjustable period of 10 to 100 ms. This timer is factory set at 20 ms. To be considered valid, the trip signal must then persist from 1 to 10 ms, adjustable, factory set for a recommended 3 ms. Both valid trip signals must arrive within 5 to 50 ms of each other to be logically ANDed and generate the trip output command. These timing checks are inhibited for any of the blocking alarms input from the G-9056 receivers. (See Trip Blocking.) When flash keying is implemented, the trip command output can be released immediately, upon return of guard, or delayed. This feature is field selectable. TRIP HOLD The G-8033E Logic Module supports a trip hold timer that can be set in the field for either 0 ms or an adjustable period between 20 and 200 ms. DEPENDABILITY AND SECURITY TESTS The G-8945 Transfer-Trip terminal, employing the G-9056 TT Receiver, has been extensively tested to document performance in noisy environments. The G-9056 circuitry is designed around a high performance, low noise sensitivity discriminator. In addition, the G-9056 provides four signal checking circuits; low level, high noise, signal-to-noise ratio, and modulation fail. All four are able to inhibit the G-8033E Logic Module and prevent the G-8945 from generating a false trip signal. The dependability and security curves shown are for 170 Hz bandwidth channels with LL and HN levels set at +/-7 db from the TP1 nominal signal level of - 30 dbm. The S/N threshold is set for an alien tone level of -36 dbm (170 Hz bandwidth) as measured at TP1. Varying these parameters directly impacts the dependability and security curves. Curves for 170 Hz channels are shown here to allow comparison to industry standards; however, it is recommended that 240 Hz channels be used since both speed and security are improved over 170 Hz channels. DEPENDABILITY TESTS In transfer-trip applications, dependability is defined as the ratio of the number of trips sent to those received, expressed as a percentage, provided that trips are received within a given period of time following each transmitted trip. Using the RFL Model 675 to key both a counter and the G-8945 terminal, the total trips sent were recorded. Trips received were also counted using a second electronic counter. The G-8033E Logic Module's guard-to-trip windows were set for 18 to 20 ms with a trip persist of 3 ms. The dependability results are shown in the following graph. The G-8945 reliably transmits 95% of all trips through a 0 db signal-to-noise ratio environment with low level, high noise and signal-to-noise detections active. DEPENDABILITY OF THE G-9056 WITH THE G-8033E LOGIC MODULE PAGE 5

6 SECURITY TESTS Security within protective relaying groups means that false trips of a breaker due to interference or malfunction are not generated by the communications terminal. The G-8945 terminal, equipped with the G-9056 TT Receiver and the G-8033E Logic Module, provides the highest security available. The outputs of the two FS channels are validated by the G-8033E Logic Module. The G-8033E performs timing checks within each channel and between the two channels. At any time, the signal checking circuitry of the G-9056 TT Receivers can disable the G-8033E Logic Module. The G-8945's most effective error detection circuitry is the in-band signal-to-noise detector (S/N). A S/N detector is located on each G-9056 TT Receiver, not on an additional module. The use of S/N detection does not lengthen the trip delay time. Once adjusted according to the filter's bandwidth, no further action is required during installation in the field. The following graph shows that, on average, the G-8945 will experience only 1 false trip in 42,300 noise bursts at a S/N ratio of -17 db. This is the worst case shown on the security performance curve and is an 11% improvement over published industry standards. This security, in conjunction with dependability of 95% at 0 db S/N, establishes the G-8945 as a secure and dependable protective relaying terminal. AVERAGE NUMBER OF NOISE BURSTS REQUIRED TO CAUSE 1 FALSE TRIP. RATIO OF rms SIGNAL OF EACH SUBCHANNEL TO WHITE NOISE MEASURED AT RECEIVER INPUT. DA-TEL GROUP RECOMMENDED CHANNEL FREQUENCIES TYPICAL SUB-CHANNEL CENTER FREQUENCY CHANNEL DELAY ( ms) HZ AT LOGIC MODULE OUTPUT (3 MS TRIP PERSIST) 170 HZ BANDWIDTH, 340 HZ CHANNEL SPACING 1 B A B A B A HZ BANDWIDTH, 480 HZ CHANNEL SPACING 4 B A B A B A HZ BANDWIDTH, 680 HZ CHANNEL SPACING 7 B A B A B A 2975 PAGE 6

7 SPECIFICATIONS POWER SUPPLY VOLTAGE Standard input potentials are 12 to 14, 21 to 28, 42 to 54 or 105 to 144 Vdc with station battery burden of less than 40 watts. A 120/220 Vac supply is available with less than 30 watts burden and an optional backup battery pack. OPERATING TEMPERATURE -20 to +60 C. COMMUNICATION CIRCUITS Balanced 600 ohms, 4-wire or 2-wire operation. TIMING SECURITY Guard presence is checked to be either 20 ms or 40 ms, strap selectable, before trip is allowed. Upon loss of the guard tone, the trip tone must arrive before an adjustable period of 10 to 100 ms. The trip signal must then persist for an adjustable 1 to 10 ms. Only after these timing requirements are met is the trip validated. SIGNAL SECURITY Low level, low signal-to-noise ratio and high noise level checks provide status to disable the trip outputs. TRIP INPUTS 10 to 15 ma derived from the station battery potential drives the optically isolated floating trip inputs. ALARM OUTPUTS The standard output is channel failure/block. Contacts rated 100 VA, 500 V, 2 amps maximum, Form-C. Contact the factory for other alarm output configurations. INPUT/OUTPUT DIELECTRIC TESTS All standard trip inputs, trip outputs, alarm outputs, communication lines and power supply inputs are isolated from ground and from the circuitry. Breakdown tests exceed 1500 Vrms, Hz, or 220 Vdc and 2500 V at 1.5 MHz in accordance with IEEE C TRANSMITTER FREQUENCY STABILITY +1 Hz, -2.5 Hz from -20 C to +65 C. AMPLITUDE DEVIATION 1.0 db maximum level change from guard to trip. OUTPUT LEVEL -35 dbm to +3 dbm at 2500 Hz, adjustable. HARMONIC OUTPUT All harmonics are better than 55 db below the fundamental. FLASH KEYING OPTION A switch enabled flash keying circuit alternately keys between guard and trip at a rate of 20 Hz when the trip input is asserted. INPUT LOGIC Key low to trip. DIAGNOSTIC INDICATORS Front panel LEDs indicate guard, trip, permissive trip sent, transfer-trip sent. RECEIVER BANDWIDTH 2% to 10% of the center frequency. 240 Hz recommended. CARRIER DETECTOR SENSITIVITY -40 dbm to -10 dbm, adjustable. INPUT FILTER Attenuates adjacent channels by better than 40 db. DIAGNOSTIC INDICATORS Front panel LEDs indicate guard or trip received, carrier present, high noise alarm, and signal-tonoise fail. DIMENSIONS AND WEIGHT The equipment can be fully contained in the G " rack-mounted module shelf. The shelf requires approximately 13" in depth and 5.25" in height. The maximum weight is 21 pounds. Other packaging options are available. SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE. CONTACT FACTORY FOR LATEST PERFORMANCE SPECIFICATIONS. PAGE 7

8 G-8945 MODULES G-8856 RELAYS. The G-8856 can be configured as a relay module or solid state output module. As a relay module 2 GEC power relays are supported with make contact ratings of 1250 VA. Alternately, the module may be configured as a solid state output for driving external relays such as the ABB RXMS-1. G-7205A SWC RELAYS. This module is intended for alarm contacts by supporting 5 Form C contacts rated 100 VA that have passed the IEEE Surge Withstand Capability tests. These contacts can be used for external alarm of any alarm condition within the shelf. In some applications these relays are also used to trip the output by controlling an interposing relay. LED indicators may be field selected to either green or red. G-8856 POWER RELAY SWC RATED CONTACTS RATED MAKE: 5 A MAX VA MAX. BREAK: 440 VDC MAX. 100 VA MAX. OPERATE TIME: 15 MS 4 MS OPTIONAL G-7205A-SWC 5 FORM C CONTACTS SWC RATED CONTACTS RATED MAKE OR BREAK: 2 A MAX. 500 VDC MAX. 100 VA MAX. OPERATE TIME: 1 MS PAGE 8

9 G-8953 SWC I/O. This module provides for input and output that is tested to the IEEE C Surge Withstand Capability standards. Two keying loop inputs and two audio terminations are supported. The keying loops are field programmable to the loop potential (12, 24, 48, 124 and 250 Vdc). Both audio terminations provide 60 Hz line filters. G-9300 FIBER OPTIC MODEM. The fiber optic modem is a shelf-mounted direct interface to fiber optic cable. A fiberbased G-8945 system allows the engineer to sidestep all associated GPR problems. The communications medium becomes a secure, EMI-free channel for improved system reliability. G-9055B TT TRANSMITTER. The G-9055B provides two FS channels which rest at the guard frequencies. When keyed they immediately shift to the trip. Keying is by two independent inputs allowing for single channel permissive applications. As a field selectable option flash keying may be enabled. Flash keying repetitively generates the guard trip keying sequence to ensure a trip is received even if the first is missed due to high noise occurring simultaneously with the trip keying. G-9056 TT RECEIVER. This module provides single channel FS detection including signal quality checks within that channel. Those checks are (1) low level, (2) high noise, (3) low S/N ratio, (4) modulation failure. Any one may be field selected to disable the transfer-trip terminal. A pre-low level alarm is also available to give external alarm for a degrading signal level before the terminal is blocked. G-8033E LOGIC MODULE. Logic checks and timing of guard trip sequences are performed by this module. During these checks a signal quality error as detected by either G-9056 receiver will block the trip output. Additionally, an adjacent channel window timer, trip-hold timer, and trip-block-status timer are provided. Both direct and permissive configurations are supported. G-9125A LEVEL OR STATUS DISPLAY. The G-9125A option provides level indication for channels A and B, 4 W receive composite, and 4 W send composite. Each is selected via a front panel rotary switch and displayed on a 10-segment LED bar graph. Also switching the rotary switch to 'ST' will display 10 status points. The status points may be field selected for latched operation. G-7800C POWER SUPPLY. The G-7800 series of DC-DC power supplies can be manufactured for any of the following station battery nominal potentials. The actual model number is also listed after the bank potential. 12 Vdc, G-7834; 24 Vdc, G-7836; 48 Vdc, G-7838; 124 Vdc, G G-9046A DIAGNOSTICS. Primarily this module allows the transfer-trip channels to be individually keyed for test purposes. It can be field set to key both channels simultaneously if required. As an option the module can be equipped to loop the terminal's send and receive lines together for a complete functional test of the local terminal. G-9045 DIAGNOSTICS. This diagnostic module is specifically for permissive transfer-trip terminals It allows the technician at one station to send a permissive trip to the second station. If held for 6 seconds or longer, a loopback trip will be sent back from the far station. An echo back time is incorporated to prevent system lock-up. PAGE 9

10 TYPICAL G-8945 TR ANSFER-TRIP RIP TERMINAL OVERVIEW AND FIELD INSTALLATION The G-8945 Transfer-Trip Terminal has several main functional blocks and two optional modules that can be installed depending on the system ordered. This description is intended to give the user the working knowledge to perform the field installation and setup. All terminal block numbers are referenced to the typical system block diagram printed on page 11. Refer to your system drawings for specific termination points. Power is supplied to the G-8945 terminal by the dc-dc power supply in the position labeled PS. Your installation block diagram shows which module is supplied for the power available at the site. Connections for the station battery are made on TB11 at the rear of the shelf. Terminal 1 is the positive (+) connection and terminal 2 is the negative (-) connection. Note from the block diagram that the 125 Vdc to the power supply also connects to the G-8856 Power Relay Module. The G-8953 Universal I/O Module interfaces the terminal to the tone lines and the keying inputs. The send line connections are made at TB1, terminals 1 and 2. This is the transmitter output from the terminal. The receive line connections are made at TB1, terminals 6 and 7. This is the tone input to the receiver section of the G-8945 terminal. On the G-8945 terminal, two keying arrangements are provided for transfer-trip and permissive-trip. Transfer-trip causes a dual channel shift for security and its input is made at TB8, terminals 1 and 2. The permissive-trip input is made at TB8, terminals 9 & 10. Note that the customer contact must be wetted with the battery voltage and that terminal 1 is positive. The G-8953 is installed in position 3 of the module shelf. The G-9055B Transmitter provides the transfer-trip tones from the keying of the G To adjust the G-9055B in the field, adjust the composite level of the transmitter while monitoring the tone level on the send line. A 600 ohm load should be present. Each transmitter can be squelched by depressing the appropriate front panel push button to check the individual tones. The receive section of the G-8945 terminal consists of two tone receivers (G-9056) that are connected to the tone receive outputs from the G Once tones are established on the receive line, the receivers can be field aligned by monitoring TP1 to TP7 of each receiver and adjusting the front panel control REC LEVEL such that TP1 is at -30 dbm. Once -30 dbm is established at TP1, the green LL indicator should be on. The CAL push-button can be depressed and the REC LEVEL adjusted so that the LL LED turns on and off as the pot is rotated back and forth. The G-8033E located in position 7 is the master logic module. The G jumper on the master logic module will be IN if redundant logic is not used and OUT if redundant logic is provided. If redundant logic is provided, all solderless jumpers on the second module should be configured exactly as those on the master logic module except jumper G. For redundant logic, jumper G of the second G-8033E should always be in or shorted. The block diagram supplied with the terminal will indicate the status of these jumpers. The transfer-trip and permissive-trip outputs of the logic modules can signal two relay modules, the G-8856 Power Relay Module and or the G-7205A SWC Relay Module. The G-8856, if included in the system, provides a high current, high voltage, high speed trip output for interfacing to breaker loads with a clearing contact. The trip outputs from the G-8856 are located on TB10, terminals 1 through 4, and consist of two normally-open contacts per trip output. The permissive outputs are terminals 5 through 8. The enable line of the G-8856 Power Relay Module is enabled through several other modules so that in the case where one critical module is removed, the power relay trip outputs are disabled. The G-7205A SWC Relay Module provides trip signaling output contacts that can be used with an interposing relay for power loads. The trip outputs from the G-7205A are available on TB5, terminals 1 through 6, and are form-c. In addition to both transfer-trip and permissive-trip, two terminal status outputs are available. The SYSTEM BLOCKED output, available at TB6, terminals 1 through 3, shows that the terminal has gone into a trip block condition, possibly from a noise or signal level problem. Also available at TB6, terminals 4 through 6, is the pre-low level alarm form-c output that gives the user a 5 to 6 db fade margin before warning that the communication circuit is degrading. A test alarm contact indicating that the terminal is in test mode is available on TB4, terminals 1 through 3. Both the G-9125A Level or Status Display Module and the G-9046A Diagnostic Module are shown. These are optional and provided to support the technician with system diagnostic tests in the field. PAGE 10

11 G-8945 TRANSFER-TRIP SYSTEM QUICK GUIDE FOR MODULE INFORMA TION G-7840C Power Supply G7840C is the Shelf Power Supply This is 1 model of 4 in the G-7800 Series Station Battery Model Fuse Vdc G-7834C 3 A FAST Vdc G-7836C 1.5 A FAST Vdc G-7838C.75 A FAST Vdc G-7840C.25 A SLO CAUTION: Turn supply off before inserting in or removing from shelf. G-8856 Relay Card Enable LED (Green) is ON when critical shelf modules are installed. Removing a G-9056 or G-8033 will disable this module. The G-8856 can be configured as a relay or solid state output module. PAGE 11

12 G-8953 Universal I/O Module LED's are on when keying loop current flowing. Module provides optical isolation of keying loop from shelf circuits plus 2 audio line termination transformers for 2500 Vdc isolation and 60 Hz notch filters. Field programmable for nominal station battery of 24, 48, 124 and 240 Vdc. G-7205A SWC Relay Module A green LED, when on, is in its normally energized state; when off, de-energized, indicating an abnormal condition. A red LED, when off, is in its normally de-energized state; when on, energized, indicating an alarm condition. G-8033E Logic Module Guard-to-trip logic and timing checked by this module. Error and output LED's may only be momentary, depending on Jumpers J, K, L and delay settings. PAGE 12

13 G-9056 T.T. Receiver (High Channel) While receiving the channel guard frequency the green mark or space LED is on. While receiving the channel trip frequency the red mark or space LED is on. All error LED's should be off when normal. Field alignment by depressing "CAL" Button and adjusting "REC LEVEL" so that "LL" LED just turns off. CAUTION: Do not adjust "HN", "LL", OR "S/N". These will impact the terminal security and dependability. G-9056 T.T. Receiver (Low Channel) G-9055B T.T. Transmitter When a DTT is sent, the DTT TX will light and remain lit until the ACK TX pushbutton is depressed. Push CH.A SQ or CH.B SQ to observe contribution of the other channel alone. PAGE 13

14 G-9125A Level or Status Display Module Level displays are real time. Status points may either follow the point or latch to hold a momentary condition. This is a selectable option. Latched points are returned to normal by pressing the ACK button on the front panel. The knob selects 1 of 4 level displays or the status display. When in service, it is recommended that the status display be left selected. G-9046A T.T. Diagnostics Module Whenever the Test-in-Progress LED is flashing the terminal is NOT in service. The 2 yellow LEDs indicate which channel (A, B or A and B) is selected to be keyed by the Trip Key momentary lever switch directly above. The Near-to-Far (normal) or Local Loop switch selects a loopback configuration which allows a terminal to send to itself for testing. This is an optional feature. Check with system documentation to see if supported by your shelf. PAGE 14

15 G-8945 ALIGNMENT PROCEDURES AND OPTIONAL SETTINGS Due to its modular design, the G-8945 Transfer-Trip (TT) Terminal can be configured to meet the specific requirements of your application. Four basic modules are incorporated in all terminals; the G-8033E Logic Module, the G-8953 Input/Output Module, the G-9055B Transfer-Trip Transmitter, and the G-9056 Transfer-Trip Receiver. This publication presents alignment procedures for these basic modules. The detailed test procedures initially discussed are for use in the test facility. These alignments are made at the factory prior to delivery as documented in the final test notes. After completion of these alignments, an abbreviated procedure is included for use in the field when commissioning a terminal into service. Before proceeding, ensure that individual module data sheets and schematics are available for reference. To facilitate adjustments and measurements, the G-8888 Breakout Module is recommended for easy test point measurement. The G-6813 Module Extender allows the operation of a module while extended from the shelf. These recommended settings and alignments ensure a security performance of 1 false trip in 42,000 noise bursts for channel bandwidths of 170 Hz, which is 'worst case' for susceptibility to noise. Da-Tel recommends the use of 240 Hz channel bandwidths for speed and improved security over 170 Hz channels. G-8033E LOGIC MODULE The G-8033E Logic Module provides a number of timing and delay functions. These are described briefly along with an adjustment procedure for each. The recommended setting is listed after the function's name. Refer to the final test data for your system for as-shipped adjustments. CHANNEL A OUTPUT CONFIGURATION S1 directs either the direct transfer-trip output, labeled DTT, or the permissive trip output, POTT, to terminal 19. If Channel A is used as a POTT, jumpers P and S perform the following options. Jumper P, when closed, allows permissive trips for a loss of guard for ms, based on the Channel A guard-trip window check. Jumper S, when closed, disables the Channel A POTT when a Channel B POTT occurs. PAGE 15

16 VALID-GUARD TIME (A AND D JUMPERS) The valid-guard check can be selected for either 20 ms (jumper A installed) or 40 ms (jumper A removed). This test requires that the guard be present for the specified period of time before the trip sequence can begin. The A jumper is used for the logic circuit on the upper channel, the D jumper is used for the lower channel. GUARD-TO-TRIP WINDOW (20 ms) This is a window of time allowed between the loss of the guard signal and receipt of the trip. Receipt of trip outside of this window is ignored. To view and adjust, key TP1 (TP4 for the B (TT) channel) to TP7 and display on the A channel of a dual trace scope. On the B channel of the scope, display TP2 (TP5 for the B (TT) channel), keyed to TP7. The duration of the positive pulse following the keying of TP1 is the guard-to-trip window. This is adjusted, using R18 (R20 for the B (TT) channel), between 10 and 100 ms. WARNING: The longer the guard-to-trip window is open, the more likely it is that a noise burst could cause a false trip output. TRIP-PERSIST TIMER (3 ms) The trip-persist timer requires that the trip signal persist for the set amount of time. A trip signal lasting less than this time will not be considered valid and resets the timer. To view and adjust, key TP1 (TP4 for the B TT channel) to TP7 and display on the A channel of a dual trace scope. On the B channel of the scope display TP3 (TP6 for the B TT channel), keyed to TP7. The duration of the positive pulse following the keying of TP1 is the trip-persist time. This is adjusted, using R24 (R26 for the B TT channel), between 1 and 10 ms. WARNING: The shorter the length of time the trip signal persists, the more likely it is that a noise burst could cause a false trip output. ADJACENT CHANNEL WINDOW TIMER (30 ms) Adjacent channel timers are provided as a further security feature. To enable the timers, jumper L must be open. To view and adjust, key the transfer-trip system and display this keying on the A channel of a dual trace scope. On the B channel, display U9:6 to TP7 and adjust R48 for the desired duration. Repeat for U9:5 and adjust R50. The possible range for these two adjustments is 5 to 50 ms. TRIP-HOLD TIMER (30 ms) The trip-hold timer ensures a minimum trip output duration. Jumper K must be installed to enable this feature. To view and adjust, key the transfer-trip system and display this keying on the A channel of a dual trace scope. On the B channel, display the trip output (jumper K or terminal 19 or 20) and adjust R46 for the desired duration. The possible range for this adjustment is 20 to 200 ms. If jumper K is removed, the trip output will last for the duration of the adjacent-channel-window timer. If jumper L is installed, the trip output will follow the keying duration at the transmit terminal. TRIP RESET TIMING (B AND E JUMPERS) Once a trip has been received, the internal trip latches of U4 can be reset either immediately upon guard or after the valid guard timing check. For resetting immediately upon guard, jumpers B and E are installed and jumpers C and F are open. For resetting after the valid guard timing check, jumpers C and F are installed and jumpers B and E are open. When flash keying is implemented at the transmitter, jumpers B, C, E and F must be removed so that the trip output does not follow the flash keying rate or immediately reset upon return to guard. TRIP-BLOCK INTERVAL (30 ms) The trip-block interval timer, enabled with jumper J, ensures a minimum blocked time during a system error. Instead of blocking the trip following the error bus, there is a minimum blocked interval lasting the duration of this timer (U8). PAGE 16

17 To view and adjust, assert the error bus (terminals 2, 3, 4, or 11) high and display on the A channel of a dual trace scope. On the B channel display jumper J to observe the timer s duration. This timer is triggered when the error bus goes out of alarm, thus ensuring a minimum error-blocking interval. Use R44 to adjust this interval between 5 and 50 ms. TRIP-BLOCK STATUS DELAY (50 ms) The trip-block status delay timer, when enabled with jumper H, ensures that intermittent errors do not cause an external alarm. Instead of the trip blocking alarm following the error bus input, the trip blocking alarm requires a minimum block interval of the duration of this timer (U12) before providing an external alarm output on terminal 13. This effectively filters out nuisance alarms. To view and adjust, assert the error bus high and display on the A channel of a dual trace scope. On the B channel display jumper H to observe the timer s duration, triggered by the error bus going into alarm. This is adjusted, using R68, between 20 and 200 ms. PERMISSIVE ON LOSS OF GUARD - OPTIONAL This is an optional configuration enabled when jumper I is installed. PERMISSIVE DISABLED DURING DIRECT TRIP - OPTIONAL Install jumper M to disable permissive output during a direct trip output. DUAL LOGIC MODULE CONFIGURATION When a system terminal requires 2 G-8033E modules for redundant logic, jumper G is installed on one module and open on the second. Refer to block diagram for instructions on jumper placement per shelf position. G-8953 INPUT/OUTPUT MODULE The G-8953 Input/Output Module does not require any timing adjustments. The only requirement is that the keying loop potential be known and the jumpers correctly installed for that potential. The straps required per battery potential are shown below. The typical output configuration for TT applications is DIR, keying the G-9055B when current is flowing in the keying loop. J2 J3 OUTPUT CONFIGURATION UN-KE YE D S TATE COLLECTOR OFF KEYED S TATE COLLE CTOR ON J1 & J4 (DIR) COLLECTOR ON COLLECTOR OFF (INV) RED #1 KEYED WHEN ON J1 J5 J6 RED #2 KEYED WHEN ON KEYING LOOP CONFIGURATION TES T S OCKET J2 & J5 KEYING VOLTS 12 J3 & J6 J PAGE 17

18 G-9055B TRANSFER-TRIP TRANSMITTER Setting the output tone level from the G-9055B is done as follows. First, in the normal application the output level is adjusted using the front panel pot labeled level. Measurement of the level typically is made at the G-8945 s audio test points on the send side of the G-8953 (TP1 and 2 or TP3 and 4). These points are 1.5 db higher than on the communications line. Once the level is adjusted the individual tones may be observed by depressing the appropriate push-button. FREQUENCY SELECTION CHART Center Bandwidth Mark Space Mark Jumpers Space Jumpers Frequency Frequency Frequency J2,3,7,8,10,11 J2,4,6,7, J2-6,10 J2,3,5-10, J1,4,6,8,11 J1,5,9,11, J1,3,5-7 J1,3,8,9, J1,2,6,7,9-11 J1,3-5,7, J1,2,4-10 J1,2,4,7,8,10, J2,4,6-9,11,12 J2,6,7, J2-5,7,9,10,12 J2,3,5,8, J1,4-6,8-11 J1,5,6,10, J1,2,8 J1,3,5-8, J2,4,9,10 J3,4,6-10, J1,7,9 J2,3,5,8,9, J2,3,4,6,10 J1,4,5,7,8,10, J1-3,6,7 J1,2,5,6,8, J1,4,5,8,9 J2-4,6,7,10, J1,2,4-10 J1,3-6,9,11 PAGE 18

19 G-9056 TRANSFER-TRIP RECEIVER The G-9056 Transfer-Trip Receiver supports an FS receiver section and 4 circuits which monitor signal integrity and noise. Factory alignment of the FS section does not require further adjustment. The FS section s operation is checked by measuring the signal level (db) and frequency at TP1 to TP7. The TP1 signal level should be -30 dbm. If not, adjust it using pot R82, labeled Receiver Level, accessed from the front panel. If a meter is not available, depress the CAL button and adjust the Receiver Level so that the low level (LL) LED just goes off. Release the "CAL" button. With the LL LED illuminated indicating carrier presence above the low level threshold, the mark and space output LED s will indicate the receipt of the guard or trip frequency. The four signal monitoring circuits have also been set to factory specifications. These are detectors for high noise, low signal-to-noise, low level, and modulation failure. Readjustment or modification, should they be required, are performed as follows. HIGH NOISE (HN) THRESHOLD (-23 dbm) With the channel tone present, raise the level by adjusting R82, Receiver Level, to -23 dbm as measured at TP1 to TP7. Next, adjust the threshold level using R20, labeled HN, so that the "HN" LED just turns on. Readjust the Receiver Level for a -30 dbm reading at TP1. The high noise detector output is connected to the error bus by jumpering J4. LOW LEVEL (LL) THRESHOLD (-37 dbm) With the channel tone present, lower the level by adjusting R82, Receiver Level, to -37 dbm as measured at TP1 to TP7. Next, adjust the threshold level using R52, labeled LL, so that the "LL" LED just turns off. Readjust the Receiver Level for a -30 dbm reading at TP1. The low level detector output is connected to the error bus by jumpering J6. The pre-low level alarm provides an alarm 2 db above the "LL" threshold and is set by R89. Once the "LL" threshold has been set, -7 db for example, R86 requires adjustment so that when the CAL button is pushed the "LL" LED just turns off. This will allow proper adjustment of the receiver's level in the field while using the "LL" as a level indicator. (See Abbreviated Field Alignment.) PAGE 19

20 SIGNAL-TO-NOISE (S/N) THRESHOLD Adjustment of the signal-to-noise detector requires an alien tone generator at the channel frequency and a frequency mixer. To perform this adjustment, the low level, high noise and modulation fail detectors must be disabled by opening J6, J4, and J8, respectively. To enable visual indication from the G-8033E error LED, install jumper J on the G-8033E Logic Module. Disconnect the normal channel tone and inject the alien tone at the channel s center frequency. An alien tone level of -36 dbm for a 170 Hz bandwidth channel is required at TP1. Add the normal channel tone, previously set at -30 dbm measured at TP1, and observe the error LED on the G-8033E Logic Module. Adjust the S/N threshold using R41 until the error LED is just off and not pulsing. Once completed, remove the alien tone and close J6, J4, J8. Reset the G-8033E s jumper J as required. MODULATION FAIL LOGIC The modulation-fail detector is a logical check of the channel s operation. During normal operation, the channel is keyed from the guard to the trip frequency. A shift from trip to guard is only normal upon the clearing of a fault. Repeated returns, more frequently than 25 ms, indicate a failure in communications. The modulation-fail detector alarms in that condition. For proper operation, the modulation-fail detector s logic must be dependent upon channel assignment, high or low. So that the trip clearing does not cause a nuisance alarm, enable the G-8033E s trip-block status delay which should be set for a longer duration than the trip-block timer. On the lower frequency channel, both switches of S1 are depressed toward the top side. On the higher frequency channel, the switches of S1 are depressed toward the bottom side. The detector s output is connected to the error bus by jumpering J8. G-9125A LEVEL OR STATUS DISPLAY MODULE The G-9125A Level or Status Display Module requires only an adjustment for the Low Level Alarm provided it is used. R40 does, however, set the calibration of the true-rms converter to match the display level LED indication. PAGE 20

21 LEVEL INPUTS Level 1 through 4 may be selected to be the source for the low level alarm detector. Installing J22 selects Level 1 as the source while J23, J24, and J25 for Level 2, 3, and 4 respectively. To adjust the alarm level, inject the threshold tone level into the selected input. Adjust R38 such that terminal 19 just becomes low, or near ground. This point will be at 12 Vdc when the tone level is greater than the adjusted threshold. STATUS INPUTS Each status input can be configured for lighting the LED when the input is high or low, adding a pull-up or pulldown to each input, or latching the LED indication when triggered. INPUT INPUT INPUT LOW HIGH PULL PULL TERMINAL LATCH NON-LATCH ASSERT ASSERT UP DOWN A J1 opn J1 cls J11 cls J11 opn J27 cls J26 cls J26 opn J27 opn B J2 opn J2 cls J12 cls J12 opn J27 cls J26 cls J26 opn J27 opn C J3 opn J3 cls J13 cls J13 opn J27 cls J26 cls J26 opn J27 opn D J4 opn J4 cls J14 cls J14 opn J27 cls J26 cls J26 opn J27 opn F J5 opn J5 cls J15 cls J15 opn J29 cls J28 cls J28 opn J29 opn H J6 opn J6 cls J16 cls J16 opn J29 cls J28 cls J28 opn J29 opn J J7 opn J7 cls J17 cls J17 opn J29 cls J28 cls J28 opn J29 opn 7 J8 opn J8 cls J18 cls J18 opn J29 cls J28 cls J28 opn J29 opn 20 J9 opn J9 cls J20 cls J20 opn J30 cls J31 cls J31 opn J30 opn 21 J10 opn J10 cls J19 cls J19 opn J32 cls J33 cls J33 opn J32 opn For continuous LED output and not latched, install J21. G-7205A-SWC RELAY MODULE PAGE 21

22 The G-7205A-SWC Relay Module does not require any adjustments. Optional jumper settings are provided to select the input keying logic and the indicator LED color. For each relay two sets of jumper blocks are provided; one set near the LED s and the other near the relay itself. Both will be labeled to correspond to the relay; i.e., J1 for K1. Jumpers are labeled A and B for blocks near the relays and C and D for blocks near the LED s. The following is a table that illustrates the jumper block settings. RELAY KEY RELAY KEY RELAY RED LED GREEN LED WITH LOW WITH +12V K1 J1-A cls J1-B cls J1-D cls J1-C cls K2 J2-A cls J2-B cls J2-D cls J2-C cls K3 J3-A cls J3-B cls J3-D cls J3-C cls K4 J4-A cls J4-B cls J4-D cls J4-C cls K5 J5-A cls J5-B cls J5-D cls J5-C cls G-9046A END-TO-END TEST MODULE The G-9046A End-to-End Test Module does not contain any adjustments. Several important options are available that must be considered. If the testing of channel A and B together, simulating a direct transfer trip, is to be enabled, close jumper J3. If channel A and B are to be keyed by only the channel A input at terminal 2, open jumper J2. LOCAL LOOP FEATURE When it is desired to loop back the local transmit into the local receivers, K2 and K3 must be installed along with the pad resistors R1 - R3 if not external. S3 on the front panel closes to enable the local loop feature. TRIP BLOCK FEATURE When it is desired to block the trip output relays when the G-9046A is in the test mode, relay K1 must be installed and enabled with jumper J1 closed. PAGE 22

23 ABBREVIATED FIELD ALIGNMENT In the field, the G-8945 terminal can require an adjustment to compensate for a tone level higher or lower than expected. Since all internal signal level adjustments were made with reference to TP1 of the G-9056, this is the only level needing correction. The correction of this level can be done simply by measuring the signal level at TP1 to TP7. The TP1 signal level should be -30 dbm. If it is not, adjust using R82, Receiver Level, accessed from the front panel. If a meter is not available, depress the CAL button and adjust the G-9056 Receiver Level so that the low level (LL) LED just goes off. Repeat for the second G-9056 Receiver. Refer to the layout shown below. Release the CAL button. No further adjustments are required. Proceed with functional tests as specified in the company commissioning procedures. DA-TEL RESEARCH COMPANY, INC. PAGE 23