Ames Fire & Waterworks 981GS Stainless Steel Single Chamber Pump Control Valve with Pressure Reducing Feature - Manual

01/06
980 Series Model
8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.amesfirewater.com
PUMP CONTROL VALVE with
PRESSURE REDUCING FEATURE
981
681
Operation
The AMES Model 981 / 681 Pump Control Valve with Pressure Reducing Feature is designed to minimize
the surges associated with the starting and stopping of pumps. The valve slowly opens and closes as
required to control pumping related surges, and throttles to maintain a maximum downstream pressure
during the pumping cycle. The pump starts and stops against a closed valve.
Pump Start Up: When the pump is signaled to start, the 3-Way Solenoid is energized, directing pressure
into the cover chamber of the 3-way Accelerator Pilot. The Accelerator Pilot allows the main valve cover
chamber to be vented downstream, causing the valve to open at a controlled rate, gradually admitting
pumping pressure into the distribution system. The rate of opening is controlled by the adjustable opening
speed control, which restricts the speed of fluid and pressure evacuating the main valve cover chamber.
Pressure Reducing Feature: During the pumping cycle, the valve acts as a Pressure Reducing Control
Valve. Throttling (Pressure Reducing) action is controlled by a normally open, pressure reducing pilot
designed to: 1) Open (allowing fluid out of the main valve cover chamber) when downstream pressure is
below the adjustable setpoint, and 2) Close (allowing fluid to fill the main valve cover chamber through the
integral orifice of the Accelerator Pilot) when downstream pressure is above the adjustable setpoint. A
decrease in downstream pressure causes the valve to modulate toward an open position, raising downstream
pressure. An increase in downstream pressure causes the valve to modulate toward a closed position,
lowering downstream pressure.
Pump Shutdown: When the pump is signaled to turn off, the 3-Way Solenoid is de-energized, venting the
cover chamber of the 3-way Accelerator Pilot. The Accelerator Pilot allows the main valve cover chamber to
be connected to upstream pressure, causing the valve to close at a controlled rate. The valve slowly begins
to close while the pump continues to operate. The closing rate of the valve is controlled by the adjustable
closing speed control, which restricts the speed of fluid and pressure entering the main valve cover chamber.
When the valve reaches the closed position, the limit switch is actuated, turning the pump off.
Hydraulic Check Feature: When the pump is turned off and downstream pressure is greater than upstream
pressure, downstream pressure is admitted to the main valve cover chamber through a check valve in the
pilot control system, closing the valve, preventing reversal of flow.
Manual Operation: Engaging the Solenoid Manual operator simulates power to the solenoid, manually
opening the main valve. Disengaging the Solenoid Manual operator returns the valve to the closed
position.