Middleby Marshall PS200 series - Manual (Page 31)

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II. TEMPERATURE CONTROLLER
The Temperature Controller is used to set and control the
oven temperature. Depending on the oven, model, the con-
troller has several functions:
•
On gas ovens with On-Off gas valve operation, the tem-
perature controller opens and closes the high flame
solenoid. This allows 100% or 0% gas flow to the burner
in response for the need for heat to maintain the set
point temperature. The temperature controller has no
effect on the low flame bypass or oven ignition.
For this operating mode, the temperature controller is set
to the On-Off Mode as described in the Kit instructions.
• On gas ovens with modulated gas valve (PID) opera-
tion, the temperature controller sends a signal to the
amplifier board which in turn controls the operation of
the modulating valve. This allows a modulated gas flow
of any necessary value from 0-100% in response for
the need for heat to maintain the set point. The tem-
perature controller has no effect on oven ignition.
For this operating mode, the temperature controller is set
to the PID Mode as described in the Kit instructions.
• On electric ovens with On-Off heater activation (includ-
ing most PS200-series and PS360-series electric ov-
ens), the temperature controller permits or cuts power
to the heating elements as necessary to maintain the
set point temperature.
SECTION 3 - SERVICING COMPONENTS
For this operating mode, the temperature controller is set
to the On-Off Mode as described in the Kit instructions.
• On electric ovens with variable pulse heater activation
(including PS555 electric ovens), the temperature con-
troller sends its signal to a controller module that con-
tains an amplifier board and two solid state relays. The
relays activate the heating elements at 100% power on
a fixed cycle time, for a length of time proportional to
the signal from the temperature controller.
For this operating mode, the temperature controller is set
to the PID Mode as described in the Kit instructions.
Note that temperature controller P/N 46837
(inc. with Service Kit 47321) includes a dedi-
cated variable pulse mode intended for the
PS536 electric oven. This special mode is NOT
used on the PS555.
• The temperature controller regulates the cooldown func-
tion. NOTE: PS200VL-series ovens do not include a
cooldown function.
• On most PS200-series and PS300-series gas ovens
(except the PS200VL), the temperature controller moni-
tors the high limit. All other oven models use a High
Limit Control Module that is independent of the tem-
perature controller.
Appendix - DIP switch settings for Conveyor Speed Controller
with Digital Display (P/N 37337), 4/02