ROC364 Instruction Manual
2-8
Master Controller Unit, I/O Module Rack, and Wiring
Rev Jun/05
2.3.2 Mounting an I/O Module Rack to a Backplate
Each I/O module rack has a male and female connector on opposite sides of the rack. The first I/O module
rack plugs directly into the MCU I/O module rack connector. Additional racks plug into each other.
Equipment and Tools Required:
Flat-blade (1/8-inch wide) screwdriver
To mount one or more I/O module racks to a backplate:
1.
Insert the connector located on the edge of the first rack into the mating connector of the MCU.
2.
Align the rack with the mounting holes in the backplate and secure in place with five 6-32
×
0.75
inch machine screws. Refer to Figure 2-4.
3.
If a second rack is required, insert the edge connector of the second rack into the edge connector
of the first rack.
4.
Align the rack with the mounting holes in the backplate and secure in place with five 6-32
×
0.75
inch machine screws.
2.3.3 Setting Voltage Jumpers in the MCU
The MCU board contains a set of three jumpers to select the nominal input voltage of either 12 or 24
volts. The factory default setting is for 12-volt operation.
Equipment and Tools Required:
None
To access the jumpers, proceed as follows:
1.
Remove the screws holding the upper MCU cover in place, and lift off the cover.
2.
Unplug any terminal blocks, connectors, and FlashPACs.
3.
Remove the two screws securing the lower MCU cover, and lift off this cover as well.
4.
Position ALL jumpers P1, P2, and P3 in either the 12-volt or 24-volt position, depending on the
nominal value of the ROC input voltage. The jumpers are located just to the right of the Power
Status indicators.
NOTE:
The 12 and 24 volt designations indicate nominal voltage values only. When
connected for 12-volt operation, the actual input voltage required for the ROC to start up is
12.5 volts dc. Once powered up, the minimum voltage required to sustain operation (low-
voltage cut-off) is 10.8 volts dc. Likewise, when connected for 24-volt operation, the start-up
voltage required is 25 volts dc, and the low-voltage cut-off is 21.4 volts dc.
5.
Replace the covers, screws, connectors, and FlashPAC.