RMC150E CPU Module Wiring

This topic covers the wiring of the RMC150E CPU Module, including the power and the discrete inputs and outputs. For wiring the discrete inputs and outputs on the DI/O UI/O modules, see the Discrete I/O Wiring and UI/O Wiring topics. See Wiring Guidelines for general wiring information.

Wire clamp screws must be tightened to max 4.5 lb-in (0.51 Nm).

Power

The RMC150E CPU requires 24VDC (20.4 – 27.6VDC).

The current rating depends on the size of the backplane:

Backplane Slots	Maximum Current
3	375mA
4	500mA
5	625mA
6	750mA

The Case pin is electrically connected to the RMC100 case.

Wiring the Communications

USB Monitor Port

Use a standard USB cable to connect to the USB port. USB connector shielding is grounded with case ground.

RJ-45 Ethernet connector

Use a standard Category 5, 5e, or 6 cable with an RJ-45 connector to connect to the 10/100 Ethernet port.

Discrete Outputs

The RMC150E CPU module discrete outputs are solid state relays. When they are ”off” they have high impedance, and when ”on” they have low impedance (50Ω maximum, 25Ω typical). The user must power the outputs externally. The maximum current and voltage for the outputs is 75 mA (50 mA for Class I, Div 2) and 30 V.

Each output has a ”+” and ”-” connection. Outputs can be wired in either a high-side or low-side configuration.

When switching inductive loads, place a diode or tranzorb across the load to protect the switch when transitioning from an ”on” to an ”off” state. Otherwise, the collapsing magnetic field can cause a reverse voltage spike in excess of the 30 V rating of the Solid State Relay.

See the RMC150 DI/O Module Wiring topic for a complete discussion of input wiring.

Discrete Inputs

The RMC150E module inputs are compatible with signal levels ranging from 12 to 24VDC. The discrete inputs draw 3mA maximum.

Note:
The RMC150E CPU inputs are 12-24V, whereas the DI/O module inputs are 5-24V.

For a complete discussion of input wiring, refer to the Discrete I/O Module Wiring topic. Notice, however, that the RMC150E CPU inputs are 12-24VDC and are not compatible with 5VDC signals.