Pressure Switch Merrill 30/50
Submersible or Jet Pump 115v or 230v
Factory Set at 30/50
Can be easily adjusted to 40/60 20/40 or any other setting.
Has separate differential adjustment to raise or lower cut out pressure without changing cut in pressure.
Important: Air Charge in pressure tank should be set to 2-4 PSI
below cut-in pressure of switch to achieve maximum drawdown of tank and
avoid short cycling of pump. The higher the pressure setting is set at
will lower the overall drawdown capacity of the pressure tank will be.
Failure to adjust the air charge properly can cause the following
Air Charge too Low: Pump will cycle frequently because the pump will come on before tank is drawn down.
Charge too High: Tank will draw down completely and pressure will drop
off before the pump kicks back on.
your switch is short cycling(rapidly turning on and off) it is probably
due to the fact that your pressure tank is failed and is not a switch
malfunction. Always check the air charge in the tank with a tire
pressure gauge with the pump off and water pressure drained from the
1/4" FEMALE PIPE THREAD
MPS3050 - Standard
MPSM43050* - w/ Pump Protection Low Pressure Cut Out
*Pump Protection Model:
will mechanically shut off power to pump if line pressure drops 10 PSI
below cut-in pressure and will need reset manually.
Lever on side
needs to be raised just enough for contacts to make until line achieves
set cut-in pressure then it can be released. This
will need to be done on start-up after switch is installed and whenever
the line pressure drops 10 PSI below cut-in pressure to protect the
well pump motor.
If lever is raised all the way up switch will turn off.
The Pump Protection Model is not recommended in installations where the pressure frequently drops 10PSI below the cut-in pressure(Ex. Old worn out Jet Pump or Undersized Pump) because it will cause frequent of nuisance trips and will need manually restarted.
Application: Water Well