The carrier type determines how bussed field power is provided. The bussed field power connectors on the horizontal and Legacy Vertical carriers differ from those on the VerticalPLUS carriers. The following section explains how to connect bussed field power to the three carrier types. Refer to Appendix M for additional information on vertical carriers.
Horizontal and Legacy Vertical Carriers
Each pair of slots on the Legacy Vertical and horizontal I/O carriers have four screw terminals for bussed field power. Two of the terminals are for the supply connection and two of the terminals are for the supply return connection.
Each bussed field power connection routes power to two adjacent I/O cards. You can use a different bulk power supply for each bussed field power connection or you can extend power to another pair of I/O cards.
The bussed field power connection provides power to two adjacent I/O cards to power field devices. Cards 1 and 2 are paired together and must use the same field voltage level. Similarly, cards 3 and 4 must use the same field voltage level, although this level can be different from cards 1 and 2.
VerticalPLUS Carriers
Each slot on the VerticalPLUS carrier has four screw terminals for bussed field power. Two of the terminals are for the + field power connection and two of the terminals are for the - field power connection. Refer to "Extending Bussed Field Power to VerticalPLUS Carriers" for the bussed field power terminal assignments.
Each bussed field power connection routes power to one slot. You can use a different power source for each bussed field power connection or you can extend power to another slot. Jumpers are pre installed at the factory to extend field power to slots 1-4. With these jumpers installed, the I/O cards installed in slots 1-4 must use the same field voltage level. Similarly, slots 5-8 have jumpers pre installed at the factory to extend field power to slots 5-8 and the I/O cards installed in slots 5-8 must use the same field voltage level. It is recommended that you use a separate power feed to each field power connector. A field power connector is the connector that connects to a bank of four I/O cards.
CAUTION!Ensure that the bussed field power connection to each carrier slot is correct for the card being installed in the slot. Card damage can result if there is a mismatch between the field power voltage at the carrier slot and the card installed in the slot.