Rosemount 8712C - Replacing the LOI Electronics

5-9
Troubleshooting
Installing the Electronics 1. Make sure that the large power supply transformer in the upper left
hand corner is present. Transmitters operating by dc power do not
have a transformer.
2. Holding the board component side down, connect the Power
Connector and the Terminal Block Connectors.
3. Connect the LOI Connector.
4. Place the board in the housing, aligning the holes with the four
standoffs. Insert and tighten the captive screws.
5. Make sure that the fuse is sized properly with the power
supply transformer.
6. Restore power to the unit and reconfigure the electronics.
NOTE
Transformers are replaced with a wiring assembly for dc powered
units (10-30 V dc).
Replacing the LOI
Electronics
Remove the LOI
Electronics Assembly
Tools for this installation
• One large Phillips head screwdriver
• One small Phillips head screwdriver
• One small flat head screwdriver
Complete the following steps to remove the LOI electronics assembly.
1. Disconnect power from the transmitter.
2. Loosen the housing cover screw and open the housing door.
3. Loosen the electronics board mounting screws and
remove the board.
4. Unsnap the LOI connector and disconnect it from the
LOI electronics.
5. Unsnap the LOI keypad connector and disconnect it from
the LOI electronics.
Input Power Fuse Size
10–30 V dc
115 V ac
230 V ac
3A
1A
½A