Installation
1-4
1-2-5
Electrical Connections
a
The diffusion pump has been designed to operate at a specific voltage. The voltage is
specified on the label that is mounted on the side of the pump. Verify the heater rating by
measuring the resistance of the heater circuit (line-to-line) and comparing it to the values in
Table 1-1, Specifications.
b
Make the electrical connections in the junction box located near the foreline. The electrical
supply should not be more than 5 percent above the rated voltage.
c
All electrical connections should be made in accordance with all applicable State, local,
and/or industrial codes.
1-2-6
Thermal Switch
a
The pump has been fitted with a manually-resettable thermal switch that is preset at the
factory. This switch is located in a box near the bottom of the pump and provides protection to
the pump in the event of excessive fluid loss, the loss of cooling water, or high inlet pressure.
b
The thermal switch is connected in series with the heater. In the event of overtemperature, the
thermal switch will open and shut off the power to the pump.
c
The thermal switch may be reset by pressing the button located at the center of the thermal
WARNING
Failure to properly connect the thermal switch circuit in the following
step could result in catastrophic damage to personnel, the pump, or the
vacuum system.
Summary of Contents for VHS-6
Page 27: ...Replacement Parts 5 2 ...
Page 28: ...Replacement Parts 5 3 ...
