Hale TPM Sistem - Manual (Page 7)

Hale Products Inc. • A Unit of IDEX Corporation • 700 Spring Mill Avenue • Conshohocken, PA 19428
Phone: 610/825-6300 • Fax: 610/825-6440 • 800-220-4253 • www.haleproducts.com
7
Increasing Pressure
a. Set TPM to a pressure (by the indicator) slightly higher than the desired new pressure
b. Put the Governor Control in the RPM mode and increase the speed to the new pressure
c. Follow Steps 4 and 5 above.
Decreasing Pressure.
a. Put the Governor Control in the RPM mode and reduce the speed to the new pressure.
b. Follow Steps 4 and 5 above.
Drafting
When operating from draft, the QG Internal Relief Valve alone is usually capable of recirculating enough
water to keep the pressure rise within 20 psig of the “set pressure”. When this valve is open, the indicator light
on the panel will be on.
Hydrant or Relay
When operating with positive suction pressure it may be necessary for the external PG30 relief valve to dump
water on the ground in addition to the water the QG relief valve recirculates in order to limit the pressure
rise above the “set pressure.” The internal QG relief valve will always open first and if it cannot handle the
pressure rise, the external PG30 relief valve will dump water on the ground. When the Internal QG relief valve
opens, the Panel light will be on and when the external PG30 dump valve opens, the indicator light on the
Panel will flash.
In some cases, when you are on the receiving end of a relay, it may help to set the pressure indicator very low
in order to limit the incoming pump pressure by dumping water on the ground before you have discharge hose
lines connected and are flowing water. Then as you are able to USE the incoming water, the PMD-relief valve
control can be moved up, to the desired operating pressure and “set” as instructed above. This technique will
also help to purge the AIR from the incoming hose and the pump before it can get to dangerous high pressure.