Greenheck 458292, Руководство по установке

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29
April 2005
®
Greenheck Waterwash Sequence of Operations
Siemens PLC S7-200, CPU 214 & CPU 224
The intent of the waterwash control panel(WWCP) is to control the operation of the fans and will start the wash
cycle upon fan shutdown. If hooked up properly, the fans will be off during wash cycles. If the exhaust fan is
being controlled by something other than the WWCP, this panel will still function. To start the wash cycle, you
must still press the “Start Fan” and “Stop Fan/Start Wash” buttons. Washing will either start immediately or
when the 24 hour timer is tripped. A fan interlock should be installed by others to keep the exhaust fan(s) from
sucking water up into the duct(s).
1. Off Mode - At the beginning of a day the following PLC lights will be lit:
Run - Should always be on
I 0.2 - Signal from fire system. Loss of this signal will initiate “FIRE” mode.
I 0.3 - Signal from wash timer (only on at time set on timer). If no timer, this will always be lit.
2. Cooking Mode - Press “Start Fan” button. The following PLC lights will be lit:
Run
I 0.2
I 0.3
- Signal from wash timer (only on at time set on timer). If no timer, this will always be lit.
Q 0.0 - Fans. Combined switching. This will control both exhaust and supply fans. Fan control relay
should be energized. Fans should be on. Optional “Cold Water Spray” solenoid should be
energized and water spraying along entire length of exhaust plenum.
Q 0.7 - Supply fan, not wired from factory. Use this if separate switching is required. Supply fan will
shut down or turn off during a fire.
3. Stop Mode - Press “Stop Fan, Start Wash” button. The fans and optional cold water spray will stop. If there
is a 24 hour or 7 day timer, the wash cycle will start at the time set on the timer. If there is no timer, the wash
cycle starts immediately. To bypass the timer and start the wash cycle immediately, you can either press the
“Start Wash” button a second time or manually trip the timer. The following PLC lights will be lit if not in wash
mode:
Run
I 0.2
I 0.3
- Signal from wash timer (only on at time set on timer). If no timer, this will always be lit.
4. Wash Mode - Sequence of Operations:
15 seconds cold water purge from piping. Detergent requires hot water.
(Optional 30 seconds)
4 minutes wash with detergent. (Optional 0 – 10 minutes)
30 seconds detergent purge to remove detergent from piping.
(Optional 1 minute)
15 minutes sequence delay to allow water heater to recover.
(Optional 0 – 45 minutes)
Repeat the above for each sequence until the last sequence is completed.
1 minute drain down to remove the majority of water from hood.
(Optional 10 minutes)
1 minute fans on to remove steam and moisture from hood.
(Optional 10 minutes)
PLC resets itself for the next days’ operation.