Honeywell SV2 Series User Manual page 164

SV2 Series Safety Shut-off Valves
APPENDIX
Burner Control Interface Wiring
IMPORTANT: If the burner management control does not have a running or lockout interlock input, consult the factory.
The valve ILKIN terminal must be powered before MV1 and MV2 valve seats can be opened or a lockout will occur.
The valve INKIN terminal must be tied to a burner management control in some manner and not simply jumpered
to L1 power
For the best Modbus communication performance, use shielded wire with two twisted pairs (Belden 9842 or
equivalent). Connect + and - to one twisted pair, and C to both wires of the other twisted pair. Connect the shield
to earth ground at the end of the connected external device (i.e. HMI, PC or building automation system). Do not
connect C to the shield. Run any noise producing wires in conduit separate from the HMI Tool and as far away from
the HMI as possible. For further Modbus wiring information, refer to the HMI installation instructions, document
32-00030.
Valve Operational Notes
After valve terminals MV1 and MV2 are powered, the valve will run internal self-diagnostics on its MV1 contact for 200-300
milliseconds and then close the contact to power the valve seats.
All SV2 Series valves have a power save feature built in. The ILKIN / ILKOUT circuit is used as a back-up to shut off the valve
through the burner control ILK circuit. If for any reason the power save feature fails, the valve internal ILK contact is opened and
a fault annunciated.
The valve internal ILK contact is closed at all times when the valve electronics are powered, unless there is a general fault
condition, a Lo-Gas / Hi-Gas pressure lockout condition from the Pressure Module, or just after power-up before internal relay
diagnostics are complete.
The valve POC (Proof of Closure) output terminal is energized when both valve seats are sensed closed and open if one or
both valve seats are sensed as not closed. On BASIC and STANDARD electronics versions, the valve POC output will remain
energized, even during a valve lockout condition.
When using the Pressure Module for the Lo-Gas / Hi-Gas limits, the software is only active after both MV1 and MV2 valve seats
are powered.
North American Standards 7800 SERIES Operational Notes
The North American Standard EC/RM78xx controls ILK (Interlock) input must close by 10 seconds into pre-purge otherwise a
recycle to the beginning of pre-purge will occur or a safety shutdown, depending on the model. The ILK input is ignored during
post-purge.
The pre-ignition input terminal (via the valve POC output) must remain closed during standby through pre-purge otherwise the
control returns to the standby state and hold for 30 seconds or a safety shutdown occurs, depending on the model.
The pre-ignition input terminal (via the valve POC output) must be closed within the first 5 seconds of post-purge or the burner
control will lockout.
If the SV2 Series Pressure Module Lo-Gas / Hi-Gas limits are set to auto reset and one of them are tripped during the burner
control Run cycle on a burner control with lockout interlocks, the burner control will lockout on ILK lockout and need to be
manually reset. This occurs since the Pressure Module is located in the ILK circuit of the valve and burner control instead of the
Limits circuit.
European Standards 7800 SERIES Operational Notes
The European Standards EC/RM78xx controls LOS (Lockout) input is monitored at all times for closure and will lockout if the
input opens, but will continue post-purge if it opens during that sequence.
The pre-ignition input terminal (via the valve POC output) must:
• not be open an accumulative time of 30 seconds during standby
164 32-00029—02