Manual Supplement
5320A Users
4 7/12
Change #8,
129
On page 6-4, prior to
Cleaning the Air Filter,
add:
Cleaning the Ground Bond Resistance and Loop/Line Impedance Relays
The power relays used in the Ground Bond Resistance and Loop/Line Impedance functions require periodic
cleaning to minimize their contact resistance. Relay cleaning should be performed once per month if the
Ground Bond Resistance or Loop/Line Impedance functions are used daily. If these functions are used less
often, relay cleaning should be performed every 90 days. If the 5320A has been powered off for more than 30
days, the relay cleaning procedure should be performed before usage.
The 5320A, with serial numbers higher than xx548xxxx, is equipped with an internal power source that
provides current during the cleaning procedure. For 5320As with serial numbers lower than 548xxxxxx, an
external power supply must be connected to the PE and N terminals. See the next section for details.
Relay cleaning is started manually from the SETUP menu, and exercises the relays on the REL board a number
of times with current flowing through them. To perform the relay cleaning procedure, disconnect all external
connections to the 5320A front panel.
Select Maintenance
Then select Relays cleaning procedure
