Edwards 30B5M, Instruction Manual, Page: 24 / 50

B064-04-880 Issue F
Page 16 © Edwards Limited 2008. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Installation
3.7.4 Thermal snap-switch connections (unconfigured pumps only)
Refer to Figure 5 . As supplied:

The two normally closed boiler protection thermal snap-switches are wired in series and are connected to
terminals 1 and 2 on terminal block TS01 (10).

The three cooling-fail thermal snap-switches are wired in series and are connected to terminals 3 and 4 on
terminal block TS01 (10).
You must connect these two circuits in series to your control equipment, in order to shut down the pump if any of
the thermal snap-switches open.
If you use a backing-pressure interlock switch, you must wire the switch in series with the thermal snap-switches.
After you have connected the thermal snap-switches (and the backing-pressure interlock, if used), close and lock the
front door of the control-box.
3.8 Fill the pump with fluid
3.8.1 Safety of vapour pump fluids
Vapour pump fluids are not dangerous when used in a pump that is operated correctly. But if the pump is operated
incorrectly and is allowed to get to very high-temperatures, the pump fluid can go through a process of thermal
breakdown. The breakdown products which result can be dangerous.
Table 2 gives more information about the
thermal breakdown of the different vapour pump fluids. Thermal breakdown is more likely to occur if the breakdown
temperature is close to the operating temperature of your pump.
WARNING
You must connect the outputs of the thermal snap-switches to switch off the electrical supply to
the pump if any of the thermal snap-switches open. If you do not, the pump may overheat and be
damaged and the pump fluid may undergo thermal breakdown.