VWR VWRC0386A, Instruction Manual

Page: 48 / 94

1. Carefully coil the extra probe lead in the compressor compartment,
and secure it to the compartment wall with a tie wrap and tie wrap
anchor provided. Additional tie wraps and anchors may be used to
secure the probe lead to the exterior back wall of the freezer.
2. Loosen the terminal screws on the solenoid. Slide the spade lug
connectors under the screws and tighten to secure.
3. Connect power to the freezer. Turn the freezer On, with battery switch
Off (O).
a.
Arming on Power On
The arming function occurs only one time at initial power-on. It
may occur in 3 ways; BUS timeout arming, both sensors fail and
BUS temperature sensor arming.
At power-on, the BUS will perform a Hold-off period check. The
BUS will not inject the refrigerant for a Hold-off period, calculated
as follows:
Hold-off period:
• 12 hour is between 0 and +70C
• 12 hour is between 0 and (BUS Setpoint - Hysteresis)
• 0 hours is below (BUS Setpoint - Hysteresis)
• 0 hours is temperature Out Of Range or both probes fail.
b. The Low Battery indicator may also illuminate.
4. Turn the battery switch to Standby mode ( ) to charge both batteries.
The following section describes the configuration and operation of the
BUS.
Warning When activated, this unit injects liquid nitrogen or carbon
dioxide. Liquid nitrogen can cause serious freezing (frostbite) if it comes in
contact with unprotected skin or eyes. Nitrogen suppresses oxygen levels
and may cause suffocation if area is not well ventilated. Refer to Appendix
A for the proper handling of liquid LN
2
.
s
7-4 Chest Freezer VWR International
Section 7
Factory Installed Options
Connect Probe/Solenoid
Harness
BUS Control Panel