![background image](http://html1.mh-extra.com/html/gardner-denver/welch-crvpro-series/welch-crvpro-series_operation-manual_3727687023.webp)
Installation
and Operation
P1700040
19
5.5.3 Change the Voltage Setting
Depending on the order number, pump are customer wired for low voltage (LV/
△
) 230-240/50Hz, 240-
265/60Hz, 200/50/60Hz or high voltage (HV/
Y
) 380-420/50Hz, 415-460/ 60Hz, 346/60Hz, the voltage
setting can be changed as followed:
1. Loosen the four screws on top of the
terminal box.
2. Lift the cover and remove it.
3. Loose the Screw of the wire port
side.
4. Attach the Three phase power wire
and Grounding wire to the binding post
and tight the screw.
5. There is PTC thermistor inside the
motor, and for safety you need to
integrate the GRB temperature control
module into the three phase power
station and connect with the motor
PTC.
6. Put the cover on the terminal box
and tighten with the four screws.
Fig. 9 Change the voltage setting
5.5.4 Motor Protection
C65 are supplied with PTC embedded three phase motor, Protect the motor and vacuum
pump from damage or destruction. The motor manufacturer makes motor PTC available as an aid to
minimize motor failure. Overload protection is a standard feature on our three-phase motor. Once the
PTC sent out temperature rise signal to the power station, then the power station will cut off the power
supply and the user should restart the power manually after pump cooling down. But to realize the
function of PTC, GRB temperature control module is needed inside three phase power station to
receive the signal by PTC. (See the part NO. for GRB temperature control module in chapter 8.1 and
8.2
). If you don’t want use PTC, appropriate motor protection switch also can realize the motor
protection function.