Installation Manual DOC-4004-5015-R1 Date: 05/27/99 Plug-in Meter Installation Manual
Document Number: Doc-4004-5015-R1 Document Release Date: 5/99 Copyright 1999 TeCom Inc. All rights reserved. No part of this publication may be reproduced, in any form or by any means, without permission in writing from TeCom Inc. The information contained in this manual is subject to change. Revisions may be issued to advise of changes or additions. InterLane is a registered trademark of TeCom Inc. Windows is a registered trademark and Windows NT a trademark of Microsoft Corporation. TeCom Inc., A TECO Energy Company 702 N. Franklin Street Tampa, FL 33602 1-800-836-9909 Fax: 813-228-1240
Measurement Configurations Contents Measurement Configurations... 4-2 Single-Phase Two-Wire... 4-3 Single Phase to Phase (no neutral)... 4-4 Single-Phase Three-Wire... 4-5 Three-Phase Four-Wire Wye... 4-6 Three-Phase Three-Wire (no neutral)... 4-7 Three-Phase Four-Wire Delta... 4-8 Meter Installation Steps... 4-9 Connecting Current Transformers... 4-9 Connecting Voltage Terminals... 4-10 Specifications... 4-11 CT Maximum Allowable Current... 4-11 Accuracy... 4-12 Meter Ratings... 4-12 Electrical... 4-12 Mechanical... 4-12 Troubleshooting... 4-13 Procedure A... 4-14 Procedure B... 4-14 Procedure C... 4-14 Procedure D... 4-15 Installation Manual 1
DOC-4004-5015-R1 Measurement Configurations This section describes different power measurement configurations with wiring connections and recommended meter models. Note: Ground wires do not carry current except in the case of a malfunction of the circuit being measured and are not used by the meter. 2 InterLane Systems (5/99)
Measurement Configurations Single-Phase Two-Wire The single-phase two-wire 120 VAC configuration is most often seen in homes and offices. The two wires are neutral and line. Any unused CT inputs must be shorted with an insulated jumper wire. Unused voltage inputs are left open (not connected) METER CHANNEL 9 OR 10 COMPONENT SIDE SWITCHES 208 480 277 240 120 VOLTAGE SELECT S1 NORM MULTI ON 1 2 MODE S2 PULSE DATA CURRENT TRANSFORMER FOLLOW LABEL FOR ORIENTATION J2 A CT B C 1 2 5 3 4 6 PHASE A DANGER- HIGH VOLTAGE VOLTAGE DELTA C A B WYE N A B J1 SHORTING WIRE 1 2 3 C 4 SINGLE PHASE TO NEUTRAL VOLTAGE SELECT, S1, SETTING V SWITCH SETTING A-N 120 120 V 277 277 V LOAD NEUTRAL LINE Figure 4.1 Single-phase two-wire connection Installation Manual 3
DOC-4004-5015-R1 Single Phase to Phase (no neutral) DANGER HIGH VOLTAGE HAZARD This configuration is dangerous because there is no neutral wire, and as a result the screw terminals to connect the CTs will have line voltages on them whenever the meter is powered. It is therefore critical for safety that the meter not be powered while connecting the CTs. For measuring a single phase to phase load (no neutral present), you can use voltage input A and B and a single CT on phase A. The CT input for unused phases B and C would need a shunt jumper across their terminals and the voltage inputs would be left open (not connected). METER CHANNEL 9 OR 10 COMPONENT SIDE SWITCHES 208 480 277 240 120 VOLTAGE SELECT S1 NORM MULTI ON 1 2 MODE S2 PULSE DATA CURRENT TRANSFORMER FOLLOW LABEL FOR ORIENTATION LOAD J2 A CT B C 1 2 3 4 5 6 PHASE A PHASE B DANGER- HIGH VOLTAGE VOLTAGE DELTA C A B WYE N A B J1 SHORTING WIRES 1 2 3 C 4 SINGLE PHASE TO PHASE (NO NEUTRAL) VOLTAGE SELECT, S1, SETTING V SWITCH SETTING A-N 208 208/240 V 240 208/240 V 480 480 V LINE Figure 4.2 Single-phase-to-phase (no neutral) wire connection 4 InterLane Systems (5/99)
Measurement Configurations Single-Phase Three-Wire This is seen in residential and commercial service with 240 VAC for large appliances. The three wires are neutral and two line voltage wires with AC waveforms 180 out of phase. This results in 120 VAC between either line wire and neutral, and 240 VAC between the two line wires. Any unused CT inputs must be shorted with an insulated jumper wire. METER CHANNEL 9 OR 10 COMPONENT SIDE SWITCHES 208 480 277 240 120 VOLTAGE SELECT S1 NORM MULTI ON PULSE DATA 1 2 MODE S2 J2 A CT B C DANGER- HIGH VOLTAGE VOLTAG DELT E C A B WY A N A B C E J1 SINGLE PHASE, 3 WIRE VOLTAGE SELECT, S1, SETTING SWITCH V A- SETTING N 120 120 V CURRENT TRANSFORMERS FOLLOW LABEL FOR ORIENTATION 1 2 5 3 4 6 SHORTING WIRE 1 2 3 4 PHASE A LOAD NEUTRAL PHASE B LINE Figure 4.3 Single-phase three-wire connection Installation Manual 5
DOC-4004-5015-R1 Three-Phase Four-Wire Wye This is typically seen in manufacturing and industrial environments. The wires are neutral and three power lines with AC waveforms shifted 120 between the successive phases. With this configuration, the line voltage wires may be connected to the phase A, B and C terminals in any order, so long as the CTs are connected to matching phases. METER CHANNEL 9 OR 10 COMPONENT SIDE SWITCHES 480 277 208 240 120 VOLTAGE SELECT S1 NORM MULTI ON 1 2 MODE S2 PULSE DATA A CT B C DANGER- HIGH VOLTAGE VOLTAGE DELTA C A B WYE N A B C THREE PHASE FOUR-WIRE WYE VOLTAGE SELECT, S1, SETTING V SWITCH SETTING A-N CURRENT TRANSFORMERS FOLLOW LABEL FOR ORIENTATION J2 1 2 5 3 4 6 J1 1 2 3 4 PHASE A 120 120 V 277 277 V LOAD PHASE B LINE PHASE C NEUTRAL Figure 4.4 Three-phase four-wire wye connection If the power for the entire wye service is being measured, three CTs must be used. This is because the entire load may be unbalanced and the neutral wire may have current flowing through it. Three CTs and a wye meter are necessary in this case. 6 InterLane Systems (5/99)
Measurement Configurations Three-Phase Three-Wire (no neutral) DANGER HIGH VOLTAGE HAZARD This configuration is dangerous because there is no neutral wire, and as a result the screw terminals to connect the CTs will have line voltages on them whenever the meter is powered. It is therefore critical for safety that the meter not be powered while connecting the CTs. This is typically seen in manufacturing and industrial environments. There is no neutral wire, just three power lines with AC waveforms shifted 120 between the successive phases. METER CHANNEL 9 OR 10 COMPONENT SIDE SWITCHES 208 O 480 277 240 120 NOR N PULS MULT M DAT E I 1 A VOLTAGE MOD 2 SELECT S ES 1 2 A CT B C DANGER- HIGH VOLTAGE VOLTAGE DELTA C A B WYE N A B C THREE PHASE THREE-WIRE NO NEUTRAL VOLTAGE SELECT, S1, SETTING V SWITCH SETTING A-C CURRENT TRANSFORMERS FOLLOW LABEL FOR ORIENTATION J2 1 2 5 3 4 6 J1 1 2 3 4 SHORTING WIRE PHASE A 208 208/240 V 480 480 V LOAD PHASE B LINE PHASE C Figure 4.5 Three-phase three-wire connection Three phase loads without a neutral present will be wired as a three phase delta regardless of the service configuration (wye or delta). Installation Manual 7
DOC-4004-5015-R1 Three-Phase Four-Wire Delta DANGER HIGH VOLTAGE HAZARD This configuration must be wired correctly. The voltage between neutral and the phase A line input must be only 120 VAC. Connect the 208 VAC "Wild Phase" to the phase C line input. This is typically seen in manufacturing and industrial environments. This configuration provides a 240 VAC three phase delta, two 120 VAC phases (to neutral), and a single 208 VAC phase known as the "Wild Phase". When wiring this configuration, take care that the phase A voltage is 208 VAC relative to neutral. METER CHANNEL 9 OR 10 COMPONENT SIDE SWITCHES 208 480 277 240 120 VOLTAGE SELECT S1 NORM MULTI ON PULSE DATA 1 2 MODE S2 A CT B C DANGER- HIGH VOLTAGE VOLTAGE DELTA C A B WYE N A B C THREE PHASE FOUR-WIRE WYE VOLTAGE SELECT, S1, SETTING V SWITCH SETTING A-N CURRENT TRANSFORMERS FOLLOW LABEL FOR ORIENTATION J2 1 2 5 3 4 6 J1 1 2 3 4 PHASE A 120 120 V 277 277 V LOAD PHASE B LINE PHASE C NEUTRAL Figure 4.6 Three-phase four-wire delta connection 8 InterLane Systems (5/99)
Meter Installation Steps Meter Installation Steps Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Step 7 De-energize electrical meters or CTs. Mount the meter on the PM4000. Place the current transformers (CTs) around the line wires of the circuit being measured. Take care to orient the CTs correctly. Install voltage wiring into enclosure. Connect the twisted white and black wires from the CT to the black terminal block on the meter, matching the wire colors to the white and black dots on the label of the meter. Jumper any unused CT inputs with an insulated shorting wire. Connect the voltage wires to the meter. The meter is powered from the A-Neutral/ C terminals. Verify that the current measurement phases match the voltage measurement phases. Connecting Current Transformers The meter only works with CTs containing built in burden resistors that produce 0.333 volts output at rated current. The use of any other CTs results in incorrect power measurements, and may permanently damage the meter. CTs with 5 amp output destroys the meter and must not be used. There are two steps to connecting the current transformers: mounting each CT around the wire to be measured and connecting the CTs to the meter. 1. Mount the CTs The meter does not measure negative power and will instead indicate zero power. CTs are directional and if mounted backwards or with their wires reversed the power will be negative. In an installation with just one CT, the meter would output zero power. In a multiple CT installation, if one CT were backwards and others were mounted correctly, then the reversed CT would cause the power on that phase to be subtracted from the power measured on the other phases, resulting in a plausible, but incorrect reading. The Magnelab CTs contain a white label stating THIS SIDE TOWARD SOURCE, or with an arrow. Mount the CT so the label faces or the arrow points towards the current source typically the circuit breaker for the circuit being measured or the utility s meter box. It is also possible to measure generated power by treating the generator as the source. The Veris CTs contain a red label stating "To Load" with arrows facing the equipment. Place the CTs around the line wires as shown in the Installation Manual 9
DOC-4004-5015-R1 Measurement Configurations. Split-core (opening) CTs may be placed around the line wires without disconnecting the wire. After a split-core CT has been placed around a wire, a nylon cable-tie should be secured around the CT to prevent inadvertent opening. In addition, the best accuracy is obtained from split-core CTs when the wire is secured away from the removable section with either a cable tie or electrical tape. Toroidal CTs require that the wire be disconnected before passing it through the opening in the CT. Always remove power before disconnecting any live wires. 2. Connect the CTs to the meter Warning! The CT inputs to the meter are sensitive to ESD (electrostatic discharge). You should ground yourself by touching the service panel case or some other grounded metal object before connecting the CTs to the meter. Route the twisted black and white wires from the CT to the meter. Any excess length may be trimmed from the wires if desired. The cable length between the CT and the meter should not exceed 20 feet. Strip or trim the wires to expose 1/4" (6 mm) of bare wire. Do not leave more than 5/16" (8 mm) or less than 3/16" (5 mm) of bare wire. The current transformers connect to the black screw terminal block. Connect each CT, with the white wire aligned with the white dot on the label, and the black wire aligned with the black dot. Note the order in which the phases are connected, as the voltage phases must match the current phases for accurate power measurement. Any unused CT inputs must be shorted. You may trim short sections off the end of the CT wires to use as jumpers. Be careful to leave insulation on the exposed portion of the jumper(s) to prevent shock or shorting danger. Finally, record the CT full-scale current as part of the installation record for each meter. If the wires being measured are passed through the CT(s) more than once, then the recorded full-scale CT current is divided by the number of times that the wire passes through the CT. Connecting Voltage Terminals Always disconnect power by shutting off circuit breaker(s) or removing fuse(s) before connecting the voltage lines to the meter. The meter must be connected to voltage lines which are protected by fuses or circuit breakers. Connect each voltage phase input to a circuit breaker on the required phase. When installing multiple meters at the same panel, it may be easier to connect voltage to a single circuit breaker. 10 InterLane Systems (5/99)
Specifications Specifications CT Maximum Allowable Current The meter uses CTs with integral burden resistors generating 0.333 VAC at rated current. The maximum allowable current is dependent only on the physical size of the CT, not the rated current. Exceeding the maximum allowable current may damage CTs. Table 4.1 AWG Wire size and amps AWG size Diameter Amps AWG size Diameter Amps 14 0.073" 20 1/0 0.380" 150 12 0.092" 25 2/0 0.420" 175 10 0.115" 35 3/0 0.475" 200 8 0.146" 50 4/0 0.530" 230 6 0.184" 65 250MCM 0.580" 255 4 0.235" 85 300MCM 0.635" 285 3 0.281" 100 350MCM 0.690" 310 2 0.295" 115 400MCM 0.730" 335 1 0.335" 130 500MCM 0.820" 380 Toroidal CT The accuracy of a toroidal CT is rated as 1% from 10% to 130% of rated current. The following toroidal CTs are available. Table 4.2 Toroidal CT amps Model ID Rated Amps Max. Amps CTT-0300-yyy* 0.30" 5, 15, 20, 30 40 CTT-0500-yyy* 0.50" 15, 20, 30, 50, 60 80 CTT-0750-yyy* 0.75" 30, 50, 70, 100 130 CTT-1000-yyy* 1.00" 50, 70, 100, 150, 200 260 CTT-1250-yyy* 1.25" 70, 100, 150, 200, 250, 300, 400 520 *yyy = rating in amps, e.g., 005, 015, 400. Split-core CT The accuracy of a split-core CT is rated as 1% from 10% to 130% of rated current. The following split-core (or opening) CTs are available. Installation Manual 11
DOC-4004-5015-R1 Table 4.3 Split-core CT amps Model ID Rated Amps Max. Amps SCT-0750-yyy* 0.75" 5, 15, 20, 30, 50, 70, 100, 150 200 SCT-1250-yyy* 1.25" 70, 100, 150, 200, 250, 300, 400, 600 SCT-2000-yyy* 2.00" 600, 800, 1000, 1200, 1500 2000 6810-yyy-0.333V 1.25" x 1.5" 30,50,70,100,125,150,200,300 500 6811-yyy-0.333V* 2.50" x 3.00" 400, 500, 600, 800 1000 6812-yyy-0.333V 2.50" x 5.50" 1000, 1200, 1500, 1600, 2000, 2400, 3000 *CT suffix (-yyy) is the rated current. Accuracy Meter Ratings The meter minimum accuracy is 0.45% of reading plus 0.05% of full-scale. The total system accuracy is subject to CT accuracy. The meter can measure power from 0.1% to 150% of full-scale power. The extra range provides measuring for occasional low and high loads. Accuracy is reduced at each end of the measuring range due to non-linear readings at low power levels and saturation at high power levels. Electrical Power Consumption: 10 VA max Maximum Operating Voltage Range: 90% to 110% of nominal Mechanical Connectors: Euroblock style terminal blocks 22 to 12 AWG, 600 V 800 4000 12 InterLane Systems (5/99)
Troubleshooting Troubleshooting SYMPTOM: The meter is reporting zero power. Probable Causes The meter is not receiving the line voltage that it needs. An unused pair of CT screw terminals has not been jumpered with an insulated shorting wire. One or more CT may be installed backwards. The voltage and CT wires may be wired out of phase. The CT rating may be too large for the application or the load being measured may not be active. The meter is not functioning correctly. Corrective Actions First, make sure that the voltage connector wiring is tight. Then, using a voltmeter, perform the following checks. For 1P and 3Y models measure the voltage between the NEUTRAL and A terminals, for 3D models measure the voltage between the A and B terminals. This voltage should be of 120-480 VAC ± 5%. On any unused CT screw terminals, connect the white and the black terminals (indicated by dots on the label) together with a short insulated jumper wire. Strip both ends of the jumper wire to expose 1/4" (5mm) of bare wire. If the CT faces the wrong direction or the white and black wires have been reversed, then the power for that phase will be negative. To verify the direction of installation, follow Procedure A below. The best approach is to visually verify that everything is wired correctly, but if that is not a feasible option, then follow Procedure B or C below. If possible, verify that at least 5% of the CT s rated current is flowing through the CT. Follow Procedure below to check the CTs. A suspect unit may be tested by disconnecting the electrical power to the PM4000 and replacing the meter with the working unit. If the suspect unit works correctly, then most likely it is the wiring to the suspect unit, and not the meter that is at fault. Installation Manual 13
DOC-4004-5015-R1 SYMPTOM: The meter is reporting an incorrect power. Probable Causes The CTs do not all have the same full-scale current rating. The CT full-scale current is incorrect. Corrective Actions Check the current ratings of all the CTs and ensure that they match. Recheck the CT s full-scale current ratings. If the wire is passed through the CT more than once, then divide the full-scale current rating by the number of times that the wire passes through the CT. Procedure A Step 1 Step 2 Step 3 Procedure B Step 1 Step 2 Step 3 Procedure C Step 1 Step 2 Remove power from the meter before working with the CT wires. Important! Observe the safety measures described in "Error! Reference source not found." on page 4-Error! Bookmark not defined.. Check each CT in turn. Disconnect all other CTs and jumper their screw terminals with a shorting wire. Provide power to the meter and check that the kwh output is not zero. If the output is zero, then reverse the CT wires (white to black and black to white) and check again. If the value is still zero, then go to "Procedure C." Using a voltmeter, verify that the voltage on the wire for the phase A CT to the Phase A voltage terminal on the meter is zero. If it is not, then determine which terminal indicates zero voltage. Repeat for Phase B and Phase C conductors, if necessary. Move the CTs to properly phase them with the voltage connections. Remove power from the meter before working with the CT wires. Important! Observe the safety measures described in "Error! Reference source not found." on page 4-Error! Bookmark not defined.. Check each CT in turn. Disconnect all other CTs and jumper their screw terminals with a shorting wire. 14 InterLane Systems (5/99)
Troubleshooting Step 3 Procedure D Step 1 Step 2 Step 3 To order the phases correctly, match each CT to the pair of screw terminals that results in the largest power. If the reported kwh output on a pair of screw terminals is zero, then also try reversing the CT wires. Throughout this test, unused CT inputs must be jumpered with a shorting wire between the white and black dots. In addition, if the kwh output of the load being measured is changing significantly, then this test may not yield correct results. Since some CTs may produce little or no output below 5% of rated current, verify that at least 5% of the CT s rated current is flowing through the CT. Use a clamp-on style current meter to measure the current in the wire that passes through the CT. If a clamp-on current meter is not available, go on to step 2. Measure AC voltage across the CT wires (probe the screw terminals). If the voltage is less than 3 mvdc, then a) less then 5% of the CT s rated current is flowing, or b) the CT is defective. If the voltage is more than 333 mvdc, then more than the CT s rated current is flowing the CT is defective, or the CT is not a 333 mv output CT. If you suspect that the CT may be defective, then a clamp on current probe may be used to verify the current flowing in the wire. If the clamp-on probe indicates that an AC current ranging from 5% to 100% of the CT s rated current is flowing and yet the voltage across the CT is not in the range of 3 to 333 mv, then the CT is probably bad. As a final test, unplug the CT screw terminals from the meter and measure the voltage again. If it is significantly different, then the meter may be defective. Installation Manual 15