Emerson ROC827 2 24-Volt DC Power Input Module PM-24, Volt DC Power Input LED Fault Indicators

ROC827 Instruction Manual

Table 3-1. 12 Volt dc Power Input Terminal Block Connections

Terminal Blocks Definition Volts DC

BAT+ and BAT–	Accepts 12 Volts dc nominal from an
	AC/DC converter or other 12 Volts dc
	supply.

ƒAbsolute Maximum: 11.25 to 16 Volts dc

ƒRecommended Operating Range: 11.25 to 14.25 Volts dc

CHG+ and CHG–	Analog Input used to monitor an external
	charging source.
AUX+ and AUX–	Supplies reverse polarity protected source
	voltage to external devices. Fused.

AUXSW+ and AUXSW– Supplies switched power for external devices.

ƒ0 to 18 Volts dc

ƒBAT+ minus ∼0.7 Volts dc

ƒ0 to 14.25 Volts dc

Table 3-2. 12 Volt DC Power Input LED Fault Indicators

Signal	LED
VOK	Green LED on when voltage is in tolerance on BAT+ and BAT–.
VOFF	Fault – Red LED on when the AUXSW+ output are disabled by
	the CPU control line.
VOVER	Fault – Red LED on when AUXSW+ is disabled due to excess
	voltage on BAT+.
TEMP	Fault – Red LED on when AUXSW+ output are disabled due to
	the excess temperature of the Power Input module.

3.1.2 24-Volt DC Power Input Module (PM-24)

Using the PM-24, the ROC827 can accept 24 Volts dc (nominal) input power from an AC/DC converter or other 24 Volts dc supply connected to the + and – terminals. Connect the input power to either or both of the

+and – channels. The 24 V dc Power Input module (PM-24) does not have CHG terminals for monitoring a charging voltage, and does not monitor the input voltage for alarming, sleep mode, or other monitoring purposes. The module has two LEDs that indicate voltage is received at the backplane and the CPU (see Figure 3-2 and Tables 3-3 and 3-4).

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 the I/O and communications modules installed in the ROC827 and any expanded backplanes. With this Power Input module installed, the ROC827 requires 20 to 30 Volts dc for proper operation.

Use the AUX+ and AUX– terminals to supply reverse polarity protected source voltage to external devices, such as a radio or solenoid.

Issued Mar-06 Power Connections 3-3