Emerson ROC827 - Manual (Page 48)

ROC827 Instruction Manual
Issued Mar-06 Power Connections 3-4
Figure 3-2. 24 Volt dc Power Input Module
Table 3-3. 24 Volt dc Power Input Terminal Block Connections
Terminal Blocks Definition Volts DC
+ and – Accepts 24 Volts dc nominal from an AC/DC converter
or other 24 Volts dc supply. 18 to 30 Volts dc
AUX+ and AUX– Supplies reverse polarity protected source voltage to
external devices. Fused. +12 Volts dc minus
∼0.7 Volts
dc
Table 3-4. 24 Volt dc Power Input LED Indicators
Signal LED
V
12
Green LED on when voltage is provided to backplane.
V
3.3
Green LED on when voltage is provided to CPU.
3.1.3 Auxiliary Output (AUX+ and AUX–)
You can use the AUX+ and AUX– terminals to supply reverse polarity
protected source voltage to external devices, such as a radio or a solenoid.
All module terminal blocks accept 12 AWG or smaller wiring. Refer to
Figures 3-3 and 3-4.
For the 12-volt dc Power Input module (PM-12), the auxiliary output
follows the voltage located at BAT+ minus ~0.7 Volts dc, which is the
protection diode voltage drop. For example, if the BAT+ voltage is 13
volts dc, then AUX+ is ~12.3 Volts dc.
For the 12-volt dc Power Input module, AUX+ / AUX– is always on and
is current-limited by a fast acting glass 2.5 Amp x 20 mm fuse. In the
event that the fuse blows, CSA requires that you replace the 2.5 Amp
fast-acting fuse with a Little Fuse 217.025 or equivalent. Refer to
“Automatic Self Tests” in Chapter 1, General Information.
V
3
LED
V
12
LED
AUX+ / AUX–
+ / –