Operating instructions

Operating Instructions for the Touch Screen Interface 61
If the Transfer Inhibit message is displayed, check for alarm messages on the Active Status window.
Correct alarm conditions before attempting a source transfer.
10.3 Enabling Remote Source Selection
If your system is equipped with the optional Remote Source Selection option, it must be enabled.
If you your system includes the Color Graphical Display:
1. Select CONFIG from the menu bar.
2. Select SYSTEM SETTINGS from the Configuration menu.
3. Select SYSTEM OPTIONS from the System Settings menu.
4. Select YES for the REMOTE SOURCE SELECT choice.
If your system contains the LED display or you are configuring the system from the RS-232 port,
see 12.1 - Using the RS-232 Port on page 70 for instructions on using the that interface.
10.4 Maintenance Bypass
The STS2 is equipped with two key-interlocked, bypass breakers, CB4 and CB5, to allow manual
bypass of the switch electronics for either input source in the event of switch failure or for mainte-
nance of the switch. Refer to the static transfer switch one-line diagram (Figure 3 on page 14).
While operating on maintenance bypass, all voltages are removed from the STS2 electronics to
facilitate safe repair, without de-energizing the load using a make-before-break switching sequence.
However, the unit can be bypassed using a make-before-break switching sequence only to the same
source to which that the switch is connected, as indicated by the highlighted static transfer switch
box on the Mimic screen.
In the event of source or switch failure, the unit should be bypassed only to the current input source.
For convenience, instructions for the bypass procedure can be displayed on the touch screen by
selecting the BYP. PROC option from the menu bar.
The Mimic is used to verify the status of the unit during the bypass procedures. In the unlikely
event that the Color Graphical Display is not available, open the front door and look through the
slots in the control door. If you can see green LEDs on the gate driver board through that slot, then
the unit is connected to the source referenced on the label below that slot. See Figure 35 on
page 62.
NOTE
The preferred source may also be changed via the optional Remote Source
Selection option, thereby initiating a transfer remotely.