Issue
- Using the same power supply (transformer) for a Xenta 527 and a 7798 I/Site
- LAN comes down and there is no communication to any other devices.
Environment
- Xenta 527
- 7798 I/Site
- 7798C
- 7798B
Cause
This is because it has blown the RS-232 expansion board on the 7798 I/Site due to a voltage overload
- The Xenta 527 must be powered with either half wave AC Power or DC power. (Half wave power connects earth ground 1 leg of the AC power to the controller.)
- The 7798B and the 7798C can use either full way power or DC power.
It is recommended to use a separate power supply for each device
Resolution
If required you can power the 7798C and the Xenta 527 on the same DC power supply, provided all devices are properly grounded. This is not recommended as each devices specifies a separate power supply.
To correctly wire these devices follow these instructions.
- You will need to send your damaged 7798 in for repair
- Add a second transformer or power supply to power the 7798 controller
- Ensure that the Xenta 527 is properly grounded.
Please reference TCON190 (page 15) for the 7798B or TCON311 (page 9) for the 7798C wiring diagrams.
Reference this cut sheet for the Xenta 527 which shows that G0 must be grounded.
