Froilabo BM 3E Essential, Руководство пользователя

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Original manual – Iss. 0.1 User manual – BM 3E Freezer 32/ 44
Connect the hose to the solenoid valve located at the rear of the freezer, then to the distribution manifold or the CO
2
cylinder, after checking that Teflon tape is applied to the thread.
Warning: If the ambient temperature is higher than +37°C, all of the CO
2
in the cylinder will be transformed to a gas.
The pressure may exceed 90 bar (temperature of +40°C). If gaseous CO
2
is injected into the freezer chamber, no
cooling effect occurs.
CO
2
detector
When CO
2
or N
2
are injected, the oxygen content in the air gradually decreases. To avoid potential asphyxiation of
personnel in the room, Froilabo can supply CO
2
detectors. An audible alarm is sounded if the oxygen level is low.
To order or install a CO
2
detector on an existing system, please contact our customer service department.
7.2.5 N
2
backup
Principle: The freezer injects liquid nitrogen (vapour phase) into the chamber if the interior temperature rises. The
solenoid valve regulates the temperature by pulsing the N
2
injection.
CO
2
solenoid valve
Connecting the N
2
option
1. Connect the N
2
hose supplied with the freezer (1).
2. Check that all couplings are properly tightened.
3. Connect the liquid nitrogen supply.
Parts to be assembled:
- ¼” copper pipe + short nut + safety valve (part
A )
- pre-assembled kit (tee piece + two male-female unions) (part B ).
1. Check that the pre-assembled kit is covered with Teflon tape.
2. Screw the pre-assembled kit onto the solenoid valve, ensuring that the tee points upwards.
3. Connect the copper pipe to the tee.
4. Attach the copper pipe to the freezer using Colson clamps, ensuring that the safety valve points downwards.
5. Check that all couplings are properly tightened.
6. Connect the liquid nitrogen supply.
7.3 Delaying temperature rises
Principle: The cryo-accumulator system is incorporated into the useful volume of the freezer and does not reduce its
storage capacity.
It provides additional autonomy before the temperature rises due to refrigeration stoppages.
For example, the time taken for the temperature in a BM 3E 690L freezer to rise from -80°C to -40°C is:
- 6½ hours without a cryo-accumulator.
- 13 hours with a cryo-accumulator.
Note: These tests were conducted with a freezer half full, at an ambient temperature of 25°C, without opening the
door.
7.4 Chart recorder
Froilabo proposes an optional chart recorder, capable of recording the temperature over a 24-hour or 7-day period
(selectable on the unit). Two models are available: disc or digital.
Description
Changing the paper disc (diagram)
1. Unlock and open the recorder door.
Lock
Clips
Chart
Stylus arm
Stylus
Knurled nut