9
SOURCES for SUPPLIES
BAGS overwrap 15 cm. wide by 30 cm. (6” x 12”) long are available from US Plastics 1390 Neubrecht
Rd. Lima OH 45801 Tel. 800 537-9724. Part #47352.
TECHNICIAN FUNCTIONS
FULL CALIBRATION
Adjust the 10-turn potentiometer so that the voltage between TP1 and Ground (Earth) is .395 V (see wiring
diagram for locations). Actual temperature calibration is then set in Programming Mode (see
PROGRAMMING MODE).
The trimmer near the BODY connector adjusts the display contrast.
SAFETY FEATURES
WATER LEVEL SENSOR
The unit will display LOW WATER and beep if there is not enough water to cover the level sensor inside the
bath, a screw located 3/4" above the temperature sensor. The heat will also turn off. The water must be
conductive in order for the level sensor to work. Use tap water or add a pinch (0.01 gr.) of salt if you are using
de-ionized or distilled water.
OVER TEMPERATURE
The unit will display TOO HOT and emit double-beeps if the temperature reaches 1.0
o
C above the thawing
temperature. The controls will turn the heaters off. In the unlikely situation that there is a component failure
and the unit continues heating, an independent safety thermostat will turn the heating off at 45
o
C.
SAFETY THERMOSTAT
An independent safety thermostat will turn heaters off if the temperature goes above 45
o
C. It has to be cooled
to 20 C to reset.
FUSING
The main fuses (Fuse-1 & Fuse-2) are located on the Printed Circuit Board and are 8Amp for 120Vac and
5Amp for 240Vac. Correct the cause of the blown fuse.
The transformer has a ¾ Amp slow blow fuse (Fuse-3) on the wires of the 12 Vac winding used to generate the
5 Vdc supply.
ISOLATION
The circuitry is isolated from the power lines by a transformer and from the heaters by an opto-coupled solid
state relay.
