Log on to rate and give feedback 1 2 3 4 5 Log on to rate
The wiring of the I/O terminals varies based on the type of I/O provided on the various modules. There are many modules that present differing combinations of the same I/O types. In describing the wiring of the I/O modules, the wiring descriptions that follow are based first on I/O type to avoid duplicating the I/O wiring information described for each of the module models.
All input types and the analog outputs (voltage and current) are based on a common ground reference. The signal ground terminals used for the common/return connection from field contacts, sensors and actuators are labeled RET. The RET terminals can be shared between multiple input or output circuits as required. It is recommended that a common signal/earth ground termination rail be provided in the enclosure. The signal return wires from the many field devices should be connected to the common signal ground/earth rail.
Whether using the RET terminals for signal return connections or using the common signal ground rail, one RET terminal on each I/O module should be connected to a common signal/earth ground rail in the enclosure using a 16 AWG wire (or larger). This is intended to provide a solid ground path connection to each of the modules for fault energy dissipation. This will better handle a possible fault in field wiring to the inputs, outputs or return connections of the I/O modules. The objective is to limit possible damage to the miswired module and avoid damaging many modules on the terminal base backplane bus.
Digital Inputs
Digital inputs are used to monitor the state of switch contacts or discrete transistor outputs on the field equipment. Each Digital Input provides a pull-up resistance which attempts to pull the input circuit up to a typical voltage (V S ) of 24 VDC. The field contacts are wired to the digital input as shown in a following diagram.
The field contacts will connect the DI input terminal to RET when they close. This pulls the 24 VDC level on the input down to near 0 V. The I/O module processor then interprets the 0 V as a closed contact.
The digital inputs can be used in pulse counter applications where the processor will count the number of times the input changes from 24 VDC to 0 V and the accumulated count is maintained as a pulse counter value for the application program.
Table: Digital Input Specifications
Item
Description
Input Range
Dry contact switch or open collector/drain, 24 VDC, 2.4 mA
Maximum ratings
-0.5 to +24 VDC
Digital Input Minimum Closure
Central IO modules: 120 ms
MP controllers: 150 ms
Pulse Input Minimum Pulse Width
20 ms
Pulse Input Maximum Frequency
25 Hz
Line Impedance Maximum
660 feet 22 AWG
Power-Limited Circuit
Supervised Inputs
Supervised inputs are used to monitor the state of switch contacts with a supervision current through the field wire loop to detect various wiring or tamper faults. Supervised input is a mode option on the Universal Inputs.
There are three different types of supported supervised input connections.
Series– Series Supervision uses a single resistor in series with the switch in the field. This type can detect tamper/trouble in the form of a short circuit across the wire pair.
Parallel– Parallel Supervision uses a single resistor in parallel with the switch in the field. This type can detect tamper/trouble in the form of an open circuit in the field wiring loop.
Series and Parallel– Series and Parallel Supervision uses two supervision resistors with one in series with the switch and the other in parallel (across the switch and resistor combination). This type can detect tamper/trouble conditions in the form of both an open and a shorted field wiring circuit.
The wiring for Series Supervision, Parallel Supervision, and dual resistor Series and Parallel Supervision is shown in a following diagram.
Each input is handled as an analog voltage input with the field circuit biased with a pull-up resistance to 5 volts. This forms a voltage divider with the field switch and resistors. The Input configuration editor supports the user definition of the field resistor value between 1 KΩ and 10 KΩ and defines voltage thresholds dividing the various, possible states of the supervised input.
Table: Supervised Input Specifications
Item
Description
5 V Circuit
1 or 2 Resistors
For 2 resistor switch supervision, both resistors must have the same value +/-5%
Monitored switch combinations
Series, Parallel, Series and Parallel
Resistor Range
1 KΩ to 10 KΩ
Line Impedance Maximum
660 feet 22 AWG
Power-Limited Circuit
Note:
The supervision described here is not specific to the smoke control application. Smoke control equipment presented on the FSCS must be supervised using positive proof techniques (end-to-end verification).
Voltage Inputs
The Universal Inputs support the selection of Voltage Input mode. When configured as voltage inputs, each of the input channels will monitor and record the DC voltage seen on the input terminal in the range of 0 to 10 VDC. Voltage inputs are wired as shown in a following diagram.
The number of monitored, voltage inputs depends on the I/O module model as discussed in the following sections.
Table: Voltage Input Specifications
Item
Description
Input Range
0 to 10 VDC
Accuracy
+/-(7mV + 0.2% of reading)
Resolution
Central IO modules: 12 bit (2.7 mV)
MP controllers: 13.3 bit (1 mV)
Input Impedance
100 KΩ
Line Impedance Maximum
660 feet 22 AWG
Power-Limited Circuit
Current Inputs
Universal Inputs support the selection of Current Input mode. When configured for current inputs, the input channels switch the input circuit to provide a 47 Ω shunt resistance. The electronics will monitor and record the voltage drop seen across the shunt resistors. The current inputs are scaled across an input range of 0 to 20 mA. Current inputs are wired as shown in a following diagram.
When configured for current input, the inputs implement a current limit protection scheme for the shunt resistor from an overload. The input current is limited to 60 mA with a serial connected FET transistor. If this limit is reached for a period of 0.5 seconds, the protection transistor is turned off opening the current input circuit. After a 5 second delay, the transistor is turned on again to attempt a new measurement.
Table: Current Input Specifications
Item
Description
Input Range
0 to 20 mA
Accuracy
Central IO modules: +/-(0.03 mA +0.4% of reading)
MP controllers: +/-(0.01 mA +0.4% of reading)
Resolution
Central IO modules: 12 bit (5.6 uA)
MP controllers: 14.29 bit (1 uA)
Input Impedance
47 Ω
Line Impedance Maximum
660 feet 22 AWG
Power-Limited Circuit
Temperature Inputs
The Universal Inputs support the selection of Temperature Input mode. When configured for temperature input, the selected input channels are internally configured for the connection of a thermistor for measurement of temperature in the field environment. The input configuration editor supports the selection from many different thermistor types that vary in resistance value and response curves. See the specification list that follows.
For installation of thermistors, the Inputs selected in temperature input mode are connected as shown in a following diagram.
Table: Temperature Input Specifications
Item
Description
Temperature Range
-50 to +150 o C (-58 to +302 o F)
Resolution
Central IO modules: 12 bit
MP controllers: 13+ bit
Line Impedance Maximum
250 feet 22 AWG
Power-Limited Circuit
Supported Thermistors
Honeywell
20 KΩ
Type I (Continuum)
10 KΩ
Type II (I/NET)
10 KΩ
Type III (Satchwell)
10 KΩ
Type IV (FD)
10 KΩ
Type V (FD w/11K shunt)
Linearized 10 KΩ
Satchwell D?T
Linearized 10 KΩ
Johnson Controls
2.2 KΩ
Xenta
1.8 KΩ
Balco
1 KΩ
Accuracy
Central IO Module: Sensor Type - 1.8 kohm, 2.2 kohm, 10 kohm, and 20 kohm
-50 to -30 °C: +/-1.5 °C (-58 to -22 °F: +/-2.7 °F)
-30 to 0 °C : +/-0.5 °C (-22 to +32 °F: +/-0.9 °F)
0 to 50 °C : +/-0.2 °C (32 to 122 °F: +/-0.4 °F)
50 to 100 °C: +/-0.5 °C (122 to 212 °F: +/-0.9 °F)
100 to 150 °C: +/-1.5 °C (212 to 302 °F: +/-2.7 °F)
MP controller: Sensor Type - 1.8 kohm, 2.2 kohm, and 10 kohm
-50 to -30 °C: +/-0.75 °C (-58 to -22 °F: +/-1.35 °F)
-30 to +100 °C: +/-0.2 °C (-22 to +212 °F: +/-0.4 °F)
100 to 150 °C: +/-0.5 °C (212 to 302 °F: +/-0.9 °F)
MP controller: Sensor Type - 20 kohm
-50 to -30 °C: +/-1.5 °C (-58 to -22 °F: +/-2.7 °F)
-30 to 0 °C : +/-0.5 °C (-22 to +32 °F: +/-0.9 °F)
0 to 100 °C: +/-0.2 °C (32 to 212 °F: +/-0.4 °F)
100 to 150 °C: +/-0.5 °C (212 to 302 °F: +/-0.9 °F)
Central IO module: Sensor Type - Linearized 10 kohm
-50 to -30 °C: +/-3.0 °C (-58 to -22 °F: +/-5.4 °F)
-30 to 0 °C: +/-1.0 °C (-22 to +32 °F: +/-1.8 °F)
0 to 50 °C: +/-0.3 °C (32 to 122 °F: +/-0.5 °F)
50 to 100 °C: +/-0.5 °C (122 to 212 °F: +/-0.9 °F)
100 to 150 °C: +/-2.0 °C (212 to 302 °F: +/-3.6 °F)
MP controller: Sensor Type - Linearized 10 kohm
-50 to -30 °C: +/-2.0 °C (-58 to -22 °F: +/-3.6 °F)
-30 to 0 °C: +/-0,.75 °C (-22 to +32 °F: +/-1.35 °F)
0 to 100 °C: +/-0.2 °C (32 to 212 °F: +/-0.4 °F)
100 to 150 °C: +/-0.5 °C (212 to 302 °F: +/-0.9 °F)
Central IO Module: Sensor Type - 1 kohm
-50 to +150 °C: +/-1.5 °C (-58 to +302° F: +/-2.7 °F)
MP controller: Sensor Type - 1 kohm
-50 to +150 °C: +/-1.0 °C (-58 to +302° F: +/-1.8 °F)
Resistive Inputs
The Universal Inputs support the selection of Resistive Input mode. When configured as resistive inputs, the input channels will measure the resistance between the input and RET terminal in the range of 10 ohms to 60,000 ohms. For installation, the resistive inputs are wired as shown in a following diagram.
The number of resistive inputs monitored depends on the model of the I/O module as discussed in the following sections.
Table: Resistive Input Specifications
Item
Description
Input Range
10 Ω to 60 KΩ
10 ohm to 10 Kohm Accuracy
+/- (7 + 4 x 10 -3 x R) ohms
Where R = Resistance in ohms
10 Kohm to 60 Kohm Accuracy
+/-(4 x 10 -3 x R + 7 x 10 -8 x R 2 ) ohms
Where R = Resistance in ohms
Resolution
12 bit
RTD Inputs on RTD-DI-16 Module
The RTD-DI-16 module supports the selection of RTD Input mode and also supports DI (Digital Input mode) when all the RTD inputs are not required.
RTD inputs include a precision current source for driving the RTD connection on the inputs allowing precision measurement of the voltage drop across the RTD elements in the field. The current varies with RTD type selection for more accurate temperature or resistance measurements.
The RTD inputs can be configured for four types of RTDs. The following table lists the types and the stimulus current used.
RTD Type
I s Current
Pt100
1.5 mA
Pt1000
0.75 mA
Ni1000
0.75 mA
LG-Ni1000
0.75 mA
The RTD inputs can be installed in a 2-wire configuration where each of the RTD connections use a single input terminal. The IN and IN/3W each service a separate RTD. The RTD module supports 16 wired RTD inputs as shown in a following diagram.
For higher accuracy and tolerance for field wire length/resistance, the RTD inputs can be installed in a 3-wire configuration where both the IN and IN/3W input terminals along with the RET terminal are used for each RTD connection.
When using a Resistance Temperature Device other than those types listed in the previous table, the inputs can be selected for 2-wire or 3-wire resistive input. Instead of converting the input to temperature, an accurate resistance measurement is performed. That resistance can then be used within the Automation Server or AS-P application program and possibly converted to other engineering units with conversion equations and/or a look-up table.
For installation, the wiring of the 2-wire and 3-wire input schemes are shown in a following diagram.
Table: RTD Temperature Specifications
Item
Description
Current open circuit voltage
4V
Supported RTDs
Pt100, Pt1000, Ni1000, and LG-Ni1000
Pt100 Range
-50 to +150 °C (-58 to +302 °F)
Pt100 Accuracy
+/-0.5 °C (+/-0.90 °F)
Pt100 Resolution
0.03 °C (0.05°F)
Pt1000 Range
-50 to +150 °C (-58 to +302 °F)
Pt1000 Accuracy
+ /-0.3 °C (+/-0.54 °F)
Pt1000 Resolution
0.03 °C (0.05°F)
Ni1000 Range
-50 to +150 °C (-58 to +302 °F)
Ni1000 Accuracy
+ /-0.2 °C (+/-0.36 °F)
Ni1000 Resolution
0.03 °C (0.05°F)
LG-Ni1000 and JCI-Ni1000 Range
-50 to +150 °C (-58 to +302 °F)
LG-Ni1000 and JCI-Ni1000 Resolution
0.03 °C (0.05°F)
LG-Ni1000 Accuracy
+ /-0.2 °C (+/-0.36 °F)
JCI-Ni1000 Accuracy
+ /-0.1 °C (+/-0.18 °F)
RTD Temperature Wiring
Maximum Wire Resistance
20 ohms/wire (40 ohms total)
Maximum Wire Capacitance
40,000 pF
Table: RTD Resistance Specifications
Item
Description
Current source open circuit voltage
4V
Power-Limited Circuit
100 Ohm Measurement
Range
50 to 220 ohms
Including wiring resistance
Accuracy
+/- (0.12 + 4 x 10 -4 x R) ohms
Where R = Resistance in ohms
Resolution
0.01 ohm
1000 Ohm Measurement
Range
500 to 2220 ohms
Including wiring resistance
Accuracy
+/- (0.7 + 2 x 10 -2 x R) ohms
Where R = Resistance in ohms
Resolution
0.1 ohm
Table: RTD Resistance Wiring
Item
Description
Maximum Wire Capacitance
40,000 pF
Shielded wires are recommended if you are wiring in a noisy, electrical environment.
RTD Inputs on MP Controllers
The MP controllers also provide support for RTD inputs. The MP controller RTD input mode provides two-wire measurements only, with a small decrease in accuracy and wire length restrictions when compared to the RTD-DI-16 module RTD inputs described above:
The maximum loop wire resistance is 40 ohms total (20 ohms on each of the two connecting wires).
The maximum wire capacitance is 60 nF.
Table: RTD Temperature Accuracy
Item
Accuracy
RTD Type: Pt1000
-50 to +70 °C: +/-0.5 °C (-58 to +158 °F: +/-0.9 °F)
+70 to +150 °C: +/-0.7 °C (+158 to +302 °F: +/-1.3 °F)
RTD Type: Ni1000 and LG-Ni1000
-50 to +150 °C: +/-0.5 °C (-58 to +302 °F: +/-0.9 °F)
Digital Output – Relay Form-A
The Relay Form-A Outputs each deliver a SPST (single-pole single-throw) Normally-Open contact pair. The contact outputs are isolated with no internal connections. The relay ratings and internal spacing provide a line voltage output rating.
The relay form-A outputs are wired as shown in a following diagram.
Table: Relay Output Form–A Specifications
Item
Description
Contact Rating (Standard relay outputs)
250 VAC / 30 VDC, 2 A, pilot duty
Contact Rating (High Power relay output)
250 VAC / 24 VDC, 12 A, pilot duty
Switch Type
Form A Relay
Single Pole Single Throw
Normally Open
Isolation (Contact to system ground)
3000 VAC
Minimum output pulse width
100 ms
Line Impedance Maximum
660 feet 14-18AWG
Nonpower-Limited Circuit
Digital Output – Relay Form-C (DO-FC Central IO Modules Only)
The Relay Form-C Outputs on DO-FC Central IO modules each deliver a SPDT (single-pole double-throw) set of three contacts including C (Common), NO (Normally-Open) and NC (Normally-Closed) contacts. The contact outputs are isolated with no internal connections. The relay ratings and internal spacing provide a line voltage output rating.
The relay form-C outputs are wired as shown in a following diagram.
Table: Relay Output Form–C Specifications
Item
Description
Contact Rating
250 VAC / 30 VDC, 3 A
Switch Type
Form C Relay
Single Pole Double Throw
Normally Open and Normally Closed
Isolation (Contact to system ground)
5000 VAC
Minimum output pulse width
100 ms
Line Impedance Maximum
660 feet 14-18AWG
Nonpower-Limited Circuit
Important:
The Nonpower-Limited relay output circuits should be separated in the enclosure and field from the other I/O circuits which are Power-Limited. The Nonpower-Limited energy source should incorporate circuit breaker protection to limit the maximum amperage to the level suitable for the wire type/size being used in the enclosure connections and field wiring.
Digital Output - Triac
The Triac Outputs each provide a solid state switch. The electrical switch function is used only with AC voltage and forms a Normally Open/Off (Form-A type) circuit. When the DO point is activated (energized), the Triac output switches ON to provide AC circuit conduction from the individual DO output terminal and a common (COMx) terminal.
The COM common terminal is typically shared with 2 or 3 Triac DO outputs. The common is typically connected to 24 VAC to provide a high-side switch that delivers 24 VAC to the activated DO terminal. The common can optionally be connected to ground to provide a low-side switch where the active DO terminal will conduct AC current, passing it to ground on the COM terminal. The choice depends on the installation environment and on whether the controlled load had ground or 24 VAC on the other side.
On the MP-C, an isolated common is provided and shared with each set of 2 Triacs. The Triac sets are isolated from each other, allowing one set to provide high-side switch and the next set to provide low-side switch, although that is not typical. On the MP-V, the 3 Triacs share one common, and this set of Triacs operate in either low-side switch or high-side switch mode.
The Triac outputs are wired as shown in a following diagram.
Table: Triac Output Specifications
Item
Description
Output Voltage/Current Rating
30 VAC, 0.25 A
Circuit Type
Normally Off/Open (Form A)
Minimum output pulse width
100 ms
Line Impedance Maximum
660 feet 14-18AWG
Power-Limited Circuit
Analog Output – Voltage
The Voltage Outputs each deliver a voltage of 0 to 10 VDC level driven by a digital to analog converter by the application program. The voltage output is intended to drive the high impedance input of an analog control device in the field (such as actuator or speed controller). The output terminal is labeled as VO in the output type wiring diagram and delivers a voltage with reference to the electrical common/ground provided on the RET terminals.
The voltage outputs are wired as shown in a following diagram.
Table: Voltage Output Specifications
Item
Description
Range
0 to 10 VDC
Accuracy
Central IO modules: +/-100 mV
MP controllers: +/-60 mV
Resolution
Central IO modules: +/-42 mV
MP controllers: +/-10 mV
Minimum load resistance
5 Kohm
Maximum load range
-1 mA to +2 mA
Terminals
Voltage Output (VO), Return (RET)
Line Impedance Maximum
660 feet 22 AWG
Power-Limited Circuit
Analog Output – Current
The Current Outputs each deliver a current of 0 to 20 mADC driven by a digital to analog converter by the application program. The current output is intended to drive the input of an analog control device in the field (such as actuator or speed controller). The output terminal is labeled as CO in the output type wiring diagram and delivers a current with reference to the electrical common/ground provided on the RET terminals.
The current outputs are wired as shown in a following diagram.
Table: Current Output Specifications
Item
Description
Range
0 to 20 mA
Accuracy
+/- 0.2 mA
Resolution
Central IO modules: +/-0.1 mA
MP controllers: +/-0.021 mA
Load range
0 to 650 ohm
Terminals
Current Output (CO), Return (RET)
Line Impedance Maximum
660 feet 22 AWG
Power-Limited Circuit
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Note:
All four are Power-Limited circuits, Not Supervised.
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Note:
All four are Power-Limited circuits, Not Supervised.
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Note:
All three are Power-Limited circuits.
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Note:
Voltage and Current Outputs are Power-Limited circuits
Relay Outputs (Form-A and Form-C) are Nonpower-Limited circuits
Not Supervised
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Note:
Triac Outpluts are Power-Limited circuits
Triac load current should be limited to 0.25 A for UL864 applications
Not Supervised
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