MGE UPS Systems STS 600A - Manual (Page 46)

Bypass Load to Source #2
1. The Source #2 SCR Switch #2 must be indicated closed on the display panel. If not, transfer the load to Source
#2 by turning the Manual Control key switch on the front display panel to the “ON” position and pressing the
Change Preferred Source Pushbutton. The STS should transfer to Source #2.
2. Open Source #1 isolation switch, CB1. (For 4-interlock system, lock and remove the key).
3. Lock Source #1 bypass switch, CB4, and remove the key.
4. Using the key(s), unlock and close Source #2 bypass switch, CB5. CB2, CB3A and CB3B (if installed) will shunt
trip, isolating the static switch section.
Return to Normal Operation (load on Source #2)
1. Close Source #2 isolation switch, CB2.
2. Wait for indication on the display panel that Source #2 SCR Switch #2 is closed.
3. Close Output isolation switch(es), CB3A and CB3B (if installed).
4. Open Source #2 bypass switch, CB5, and lock.
5. Close Source #1 isolation switch, CB1. (For 4-interlock system, remove key from CB5 lock to unlock CB1, and
close CB1).
Test Mode (Except with 4-Interlock System)
1. Bypass the load to Source #1 or #2 (see above procedures).
2. Close both source isolation switches, CB1 and CB2.
3. The static switch may now be tested without disturbing the load.
CAUTION: EXPOSURE TO HAZARDOUS VOLTAGES.
Dangerous voltage levels are still present inside the
STS cabinet. When bypassed/isolated, control power
supply circuits are still live and power is provided for
indicator lights and emergency power off circuits.
Disconnect all sources of power before servicing.
Refer servicing to qualified service personnel.
Epilson STS TM
Installation 3 —8 86-504004-00 B03