Siemens SED2 VFD Electronic Bypass Option 125-3208 - Manual (Page 52)

SED2 VFD Electronic Bypass Option Operating Instructions
44 Siemens Building Technologies, Inc.
Interlock
Description
The Interlock feature (also called damper end switch logic) enables the SED2 outputs
to inhibit motor start until a safety condition (proofing sequence) is confirmed. Any
call to start the motor from the SED2 or bypass does not directly start the motor, but
instead initiates the following Interlock procedure:
• The Interlock Start Logic Enable indicator is ON. Proofing is required to start
in VFD or bypass mode.
• The Interlock Start Logic Command indicator turns ON and the Proofing
indicator flashes.
• When in VFD mode, the SED2 Relay closes and the Controller board
Programmable Output closes to initiate the proofing sequence. The
Programmable Output relay is used to supply power to an external device
such as a damper actuator.
• When not in VFD mode, the Controller board ignores the SED2 Relay.
• When in bypass mode, any call to start the motor in bypass (in either hand
bypass or auto bypass) initiates the proofing sequence. The Programmable
Output closes and is used to supply power to an external device such as a
damper actuator.
• When control of the external device (such as a damper actuator) is satisfied,
it must supply a contact closure to the Controller board Interlock Start. The
Interlock Start Logic Command indicator turns OFF and the Proofing
indicator turns ON. The motor then starts in the selected mode.
• Any call for the motor not to be running requires a new proofing sequence to
be initiated.
NOTE: This feature can only be used with a hardwired start/stop command.
Settings
The Interlock feature requires that Controller board DIP
Switch 3 is set ON.
NOTES:
1. The Interlock Start Logic Enabled indicator is on
steady.
ON
12
5
34
12
5
34
ON OFF
SW1
VFD0118R1