Emerson ROC827 Power Input Module Descriptions, 1 12-Volt DC Power Input Module PM-12

ROC827 Instruction Manual

Chapter 3 – Power Connections

This chapter discusses the Power Input modules. It describes the modules, explains how to install and wire them, and provides worksheets to help you determine—and tune—the power requirements for the I/O and communications modules you can install in the ROC827 and the EXPs.

In This Chapter

3.1	Power Input Module Descriptions	3-1
	3.1.1 12-Volt DC Power Input Module (PM-12)	3-1
	3.1.2 24-Volt DC Power Input Module (PM-24)	3-3
	3.1.3 Auxiliary Output (AUX+ and AUX–)	3-4
3.2	3.1.4 Switched Auxiliary Output (AUXSW+ and AUXSW–)	3-6
	Determining Power Consumption	3-7
	3.2.1 Tuning the Configuration	3-11
3.3	Removing a Power Input Module	3-20
3.4	Installing a Power Input Module	3-21
3.5	Connecting the ROC827 to Wiring	3-21
	3.5.1 Wiring the DC Power Input Module	3-22
	3.5.2 Wiring the External Batteries	3-23
	3.5.3 Replacing the Internal Battery	3-25
3.6	Related Specification Sheets	3-26

3.1Power Input Module Descriptions

As a ROC800-Series controller, the ROC827 uses a Power Input module to convert external input power to the voltage levels the ROC827’s electronics require. The module also monitors voltage levels to ensure proper operation. Two Power Input modules—12 V dc (PM-12) and 24 V dc (PM-24)—are available for the ROC827.

The power consumption of a ROC827 and any attached expandable backplanes determines the current requirements for the external power supply. Refer to Section 3.2, “Determining Power Consumption” for a discussion and worksheets on assessing power requirements.

The Power Input module has removable terminal blocks for wiring and servicing. The terminal blocks can accept wire sizes 12 AWG (American Wire Gauge) or smaller.

3.1.1 12-Volt DC Power Input Module (PM-12)

Using the PM-12, the ROC827 can accept 12 Volts dc (nominal) input power from an AC/DC converter or other 12-volt dc supply. The input source should be fused and connected to the BAT+ and BAT– terminals (see Figure 3-1). The base system (CPU, power input, and backplane) requires less than 70 mA. The Power Input module economizes power consumption using 3.3 Volts dc switching power that provides power to

Issued Mar-06 Power Connections 3-1