Shellab 74200-720 - Manual (Page 8)

Microprocessor Control Bead Baths 8
CONTROLS OVERVIEW
This section provides an overview of the panel controls. See Figure 1 for an illustration of the panel
controls.
Figure 1. Control Panel
Power Switch
The Green I/O (On/Off) power switch controls all power to the unit. It must be in the I position to be ON
and the green power on light illuminated before any systems are operational. The on/off switch must
remain easily accessible at all times.
Main Temperature Controller
This control consists of the digital display and UP and DOWN arrow pads for inputting set point
temperatures and calibration.
Fuses
The fuses are located at the back of the unit within the power inlet plug and 220v units also have a fuse
holder located next to the inlet. The fuses act as a circuit breaker and will cut off power to the unit if there
is an electrical surge or malfunction. The fuses must be in place for the unit to operate. Please contact
customer service for more information.
Over Temperature Thermostat (OTL)
This controller is marked “Safety” and is completely independent of the Temperature Controller. The OTL
guards against any failure of the Temperature Controller that would allow the temperature to rise past set
point. If the temperature rises to the OTL set point, the OTL takes control of the heating element and
allows continued use of the bead bath until the problem can be resolved or service can be arranged. The
OTL is manually adjusted with a screwdriver or coin so accidental adjustment cannot occur.
Heating Activated
This light is ON when the Temperature Controller has activated the heating element to reach and maintain
set point.
Over Temperature Activated Light
This light is ON when the Over Temperature Thermostat has been activated. Under normal operating
conditions this light should never be on.
Section
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