SIGNAL INTERFACE MODULE FEATURES Optically isolated inputs Field adjustable output Second onboard DC supply Positive / negative voltage output APPLICATIONS Phase cut to ma / VDC conversion Signal scaling or inverting High / low signal selection Averaging or summing of 2 signals DESCRIPTION SPECIFICATIONS SIZE: 3.5" L x 3" W x 1" H The was designed as a signal interface module to convert, scale, select, sum, or average two input signals. The inputs on the may be factory configured to accept phase cut, 4 to 20mA, 0 to 10V DC or other custom signals. It has one optically isolated input or two nonisolated inputs, an on-board full-wave bridge rectifier and a half-wave bridge rectifier. A second DC supply is available to power sensors, transmitters or other input devices. The has a ZERO and SPAN potentiometers with only minimum interaction so that the zero can be adjusted for final signal calibration. The output may be configured for 0 to 15V DC and any voltage in between, 4 to 20mA, and other custom output signals. OPERATION The circuit board houses both a 24V AC full wave bridge rectifier and a halfwave rectifier for 24V AC/DC power supply input, two positive regulated and one negative reference power supplies, input section, amplifier section and output section. The input section can be configured for one optically isolated input or two non-isolated inputs. Signals from the two non-isolated inputs can be summed, averaged or high/low selected. If optical isolation is selected, the signal passes through a 4N35 optical isolation IC and is amplified. There is no electrical connection between the input and output. A thermistor provides temperature compensation to improve the linearity of the 4 to 20mA isolated input. If nonisolated input is selected the input common and output common are connected and share the same potential. MOUNTING: POWER: 3" RDI snap-track (supplied) 24V AC, ±10%, 50/60Hz, 2VA 24V DC @ 50mA ( filtered DC) ISOLATED INPUTS: 0-20V phase cut, 4-20mA, NON-ISOLATED INPUTS: 0-5V DC, 0-10V DC, 3.75-2.25V DC, RTD S, AD590, Thermistors, 135Ω INPUT IMPEDANCE: <500Ω for 4-20mA >2KΩ for 0-20V phase cut >10KΩ for voltage inputs OUTPUT: 4-20mA DC, max of 500Ω, 0-10V DC, 2KΩ minimum ADJUSTMENTS: ZERO & SPAN ± 20% AMBIENT TEMP: 0 to 50 C. WIRING CONFIGURATION The amplifier section provides both zero and span adjustments and direct or reverse output action. If 4-20mA output is selected, then the output of the amplifier section drives a negative referenced current loop transmitter consisting of an LM358 and output transistor.
SIGNAL INTERFACE MODULE ORDERING INFORMATION /XXX/XXX/X INPUT CODE OPTIONS Function Option Code Output Option Code Input Option Code PC - 10-90% phase cut MA - 4-20mA analog isolated VDC - Analog DC voltage (specify) OHMS - 3 wire 0-135Ω or larger pots. AD590 - Linear temperature sensor (specify temperature range) RTD - RTD 100/1000Ω temperature sensor (specify temperature range) OUTPUT CODE OPTIONS ma - 4-20 Ma, DC VDC - DC voltages - specify 5VDC - 0 to 5V DC 10VDC - 0 to 10V DC KL - 3.75 to 2.25V DC SM2-3.12 to 1.87V DC BC-X - 3,6,9,12,or 15V DC FUNCTION CODE OPERATION PHYSICAL CONFIGURATION TYPICAL APPLICATION D - Direct Operating R - Reverse (0 to 10 in, 10 to 0 out) H - High Select of two inputs L - Low Select of two inputs A - Average two inputs S - Summing of two inputs CALIBRATION ADJUSTMENTS Output adjustments are made with the ZERO and SPAN potentiometers on the main module. A clockwise ZERO adjustment increases the output level and should be made with a 0% input signal. A clockwise SPAN adjustment increases the signal differential and should be made with a 100% input signal. ORDERING CODE EXAMPLES Note: Multiple inputs and outputs are shown but are not simultaneous. When the output signal feeds a device that is powered externally for panel power, it is imperative that this card be powered from an ungrounded isolated 24VAC source or damage could result in both the and the device its signal is fed to. /PC/MA - 0 to 20V phase cut isolated input, 4 to 20mA output /PC/KL-VDC/R - 0 to 20V phase cut isolated input, 3.75 to 2.25V DC reverse ramp output /MA/MA/SC - 4 to 12mA isolated input, 4 to 20mA output (scaled) /10VDC/10VDC/L - Two, 0 to 10V DC non-isolated signals, low select, 0 to 10V DC output /135Ω/MA - 0 to 135Ω 3-wire potentiometer, 4 to 20mA output /KL-VDC/KL-VDC/H - Two, 3.75 to 2.25V DC input signals, high select 3.75 to 2.25V DC output
APPLICATION 1 - PHASE CUT TO VOLTAGE CONVERSION The /PC/VDC converts STAEFA s phase cut signal (10 to 90%) to a 0 to 5V DC output signal. The s phase cut input is optically isolated. When passing a control signal from one Smart II to another, a 24V AC isolation transformer is recommended or power the from the second Smart II s AUX supply. This maintains the input isolation on the second Smart II. When the s output is fed to a device (such as VFD's, chillers, etc.) that has its input common tied to earth ground and the panel Transformer s secondary is grounded due to local electrical codes, the should be powered using terminal 9 & 10 observing polarity. APPLICATION 2 - PHASE CUT TO MA CONVERSION The /PC/MA converts phase cut (10 to 90%) to a 4-20mA signal. The s phase cut input is optically isolated. When the s output is fed to a device (such as VFD's, chillers, etc.) that has its input common tied to earth ground and the panel Transformer s secondary is grounded due to local electrical codes, the should be powered using terminal 9 & 10 observing polarity or use an isolation transformer to avoid ground loop problems. Both zero and span adjustments allow for field calibration. APPLICATION 3-4-20MA ISOLATION OR SIGNAL SCALING The /MA/MA can be set up for either 4-20mA isolation or 4-20mA isolation with scaling. The 4-20mA signal is fed into an optically isolated input. A 24V AC isolation transformer is recommended to maintain isolation. Output action can be either direct or reverse. Scaling is available 1 to 2 for 4-12mA or 12-20mA input with 4-20mA output. For dual scaled outputs see DIA08.
APPLICATION 4-2 INPUT, HIGH/LOW SELECT, SUMMING OR AVERAGING The /2MA/VDC-X or /2VDC/VDC-X can be factory set up to receive two non-isolated signals and either select the highest or lowest 4-20mA or voltage, and sum or average the two signals to give you a voltage or 4-20mA signal output. Voltage application shown, 4-20mA converted to 1-5VDC thru 250 ohm dropping resistor. If more inputs are needed, see the SIA07A interface module. APPLICATION 5 - RESISTANCE INPUT TO VOLTAGE OR MA OUTPUT The /OHMS/MA or VDC interface module can be set up for resistance inputs. A second voltage regulator is added to the to provide a 6V DC supply which is used with 3-wire potentiometers. This application could be used to provide a manual positioning potentiometer or to read the damper position from a feed back potentiometer and generate a 0-5V DC, 0-10V DC or 4-20mA output signals. APPLICATION 6 - SIGNAL SPLITTING The /VDC/VDC-SC or /MA/MA-SC can be scaled to provide a full output signal of 0-10V DC or 4-20mA over half the range of an input signal. The action can be either reverse or direct, permitting two controlled devices to be sequenced from the same input signal. In the case of 4-20mA input, the input isolators are connected in series.
APPLICATION 7 - milli-volt INPUT SIGNAL SCALING The /mv/vdc or ma can be set up for either Voltage or 4-20mA output with scaling. The 0 to 30mV signal is fed into a high impedance input and is scaled to the desired voltage or current output. In this example the and Digital Display are powered for the aux 12 volt supply from the controller. An optional 24V AC isolation transformer can be used instead of the Aux supply. If isolation is required to avoid or eliminate ground loop problems, the SIA08 is recommended. APPLICATION 8 - ± 15VDC INPUT SIGNAL SCALING The /±15V/VDC or ma can be set up for either Voltage or 4-20mA output with scaling. The -15 to +15VDC signal is fed into a high impedance input and is scaled to the desired voltage or current output. In this example the and Digital Display are powered for the aux 12 volt supply from the controller. An optional 24V AC isolation transformer can be used instead of the Aux supply. If isolation is required to avoid or eliminate ground loop problems, the SIA08 is recommended. APPLICATION 9- AVERAGE OF TWO VOLTAGE INPUTS WITH 24V DC SUPPLY The /2VDC/5VDC/A is set up for two 0-10V DC Voltage input signals and provide an average of the two scaled to 0-5V DC. Both the 0-10V transmitters and the are powered by a 24V DC power supply. NOTE that the transmitters are wired in a 3 wire configuration, power supply common is common for the output signal.