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Instruction Manual
2.6.7 Pressure Relief Valve (PRV)
Maximum safety and reliability may be ensured by
protecting liquid ends and piping with an external
pressure relief valve installed in the system
discharge line. Although the pump is protected
against excessive pressure by an internal relief
valve, to prevent a blocked discharge line from
causing damage to the piping or process equipment,
install a Milton Roy pressure relief valve in the pump
discharge line. This valve is designed and sized to
handle system flow rates and pressures safely
while resisting corrosion by the process liquid.
Install the safety valve in the discharge line
between the pump and the nearest shut- OFF
valve. (This will prevent potential system damage
from accidental valve closure.) Pipe the pressure
relief valve outlet back to the suction tank or to
drain, but in either case ensure that the pipe end
is continuously visible so pressure relief valve
leakage may be detected. Milton Roy pressure
relief valve must be installed in accordance with its
user manual top of supply tank in order to function
properly.
2.6.8 Check Valves
A check valve should be installed at the point
where the discharge line enters a boiler or other
high-pressure vessel. This will prevent back flow
through the discharge piping and will isolate the
pump discharge from system pressures (a safety
consideration).
2.6.9 Shut- OFF Valves
In order to isolate the pump during maintenance,
provide shut- OFF valves in both suction and
discharge lines next to the pump. Locate discharge
line shut- OFF valve downstream from the inlet
connection of the safety valve.
Figure 4
shows
recommended valve locations.
2.7 ELECTRICAL CONNECTIONS
Ensure that the electrical supply matches the pump
motor nameplate characteristics. Before operating
the pump, check the direction of rotation of the
motor to be sure it matches the direction of the
arrow stamped on the motor (rotation should be
clockwise when viewed from the top of the motor).
If motor rotation is incorrect, refer to the motor
data plate or motor manufacturer’s instructions
for reversing.
OPERATION WITH THE WRONG
MOTOR ROTATION WILL DAMAGE
THE PUMP AND MOTOR AND VOID THE WARRANTY.
DO NOT FORGET TO CONNECT
THE PUMP TO AN EARTH
GROUND!
Electric protection of the motor (fuses, overload
meters or relays) should correspond to the rated
current indicated on the motor data plate.
SECTION 2 - INSTALLATION
