Series 125 Pump Control

Valve Features

• Operates automatically off line pressure.
• Heavy-duty, nylon-reinforced diaphragm.
• Rectangular-shaped, soft seat seal provides drip-tight Class VI closure.
• Diaphragm assembly Guided top and bottom.
• Throttling seat retainer for flow and pressure stability.
• Easily maintained without removal from the line.
• Replaceable seat ring.
• Alignment pins assure proper reassembly after maintenance.
• Valves are factory tested.
• Valves are serial numbered and registered to facilitate replacement parts and factory suppo

125 BOOSTER PUMP CONTROL

Models 125 and 125-27, designed primarily for booster pumps, are installed inline, on the discharge of the pump. These valves also include a check feature that eliminates any need for a separate pump check valve.

126 DEEP WELL PUMP CONTROL

Valve Operation

*Lift check closes valve before pressure reversal

Model 125 and 125-27, designed primarily for booster pumps, are installed inline, on the discharge of the pump. They are normally closed with the pump off, open slowly after the pump starts, and close slowly prior to pump shutdown. In this way, flow is slowly and smoothly transitioned to and from the system. These valves also include a check feature that will close the valve in the event of a power failure while the pump is running. Thus, they eliminate any need for a separate pump check valve.

Model 126, designed for deep well pumps, is installed on a bypass line between the pump discharge and the pump check valve, and discharges either to waste or back into the well itself. It is normally open with the pump off, closes slowly after the pump starts, and opens slowly prior to pump shutdown. In this way, flow is slowly and smoothly transferred from the bypass to the system, and vice-versa.

Wiring Diagram

ELECTRICAL

A certain amount of components and wiring is required to interface the valve and pump. The wiring diagram below is typical for Series 125. Series 126 is similar but with minor variation to the limit switch. (consult factory for specific diagram) To make the interface quick and simple, the OCV Pump Commander may be added to your installation. This pre-wired controller is available in various models depending upon the level of control sophistication required.

TYPICAL WIRING PROGRAM

SERIES 125;

SOL  =  SOLENOID PILOT (ON VALVE)
LS  =  LIMIT SWITCH, SPDT (ON VALVE)
CR1,CR2  =  CONTROL RELAY, DPDT
TD1*  =  TIME DELAY RELAY, DPDT, ON-DELAY
TD2**  =  TIME DELAY RELAY, DPDT, ON-DELAY (OPTIONAL)
HOA  =  HAND-OFF-AUTO-SWITCH
RS  =  REMOTE START SWITCH
MSR  =  PUMP MOTOR STARTER RELAY

*TD1 shuts pump down if valve does not open
**TD2 if used, delays valve opening for predetermined time period

Sizing

SIZING OF SERIES 125 Valves – Booster Pump Control

1. Decide whether a globe or angle valve will best fit your installation. Keep in mind that it is always best to install any control valve “bonnet up,” particularly in sizes 8” and larger.
2. Begin with a line sized valve, i.e, the same size as the pump discharge. Calculate the pressure drop from the formula, where:
   

   DP = pressure drop, psi sg = specific gravity of line fluid (water = 1.0) Q = rated flow of pump, gpm Cv = Valve coefficient from Table 2.

3. The pressure drop calculated is that for a wide-open apply and would be true for the dual-chambered 125-27 valve regardless of flow rate. On the other hand, the single-chambered valve may not be wide open. Refer to the “wide open at” column of Table 2. If the flow rate is less than this figure, the pressure drop of the single-chambered valve can be 2-3 psi higher than the value calculated in Step 2. If the flow rate is higher than the figure given, the single-chambered valve will be wide open and will have a pressure drop equal to the dual-chambered valve.
4. Check to see that the flow velocity does not exceed 20 ft/sec. If it does, or if the pressure drop is excessive, consider using the next size larger valve.
5. Finally, if the 125-27 valve is selected, make note of the diaphragm chamber discharge. This quantity of water will be discharged to atmosphere each time the valve opens or closes. Provision should be made to drain or otherwise dispose of this water.

FLOW CHARACTERISTICS

Sizing of Series 126 Valves – Deep Well Pump Control

1. Decide whether a globe or angle valve will best fit your installation. Keep in mind that it is always best to install any control valve “bonnet up,” particularly in sizes 8” and larger.
2. Carefully examine your pump curve. Make note of the flow rate at which the pump discharge pressure is reduced to a point just below system static pressure.
   Calculate the required valve CV from the formula where:

   Q = flow rate as determined in Step 2, gpm PS = system static pressure, psi sg = specific gravity of line fluid (water = 1.0)

3. Using either the globe or angle valve column of Table 2, pick the smallest size valve that has a CV at least equal to that calculated in Step 3.
4. Using the flow rate determined in Step 2, make sure the velocity does not exceed 30 ft/sec.
5. Finally, make note of the diaphragm chamber discharge. This quantity of water will be discharged to atmosphere each time the valve opens or closes. Provision should be made to drain or otherwise dispose of this water.

Valve Selection Guide

By combining various control pilots, multiple valve functions can be performed on a single Series 125 or 126 Pump Control Valve. To find the combination function valve, select the desired features and then the model number. This chart shows only a sample of those most often specified valves. Consult the factory for specific data on the model you selected.

Combination valves can often reduce or eliminate other equipment. Example: If the system requires a Pump Control and a Pressure Sustaining Valve, the sustaining feature can be added as a function of the Pump Control Valve, Model 125-13.

Material Specifications

Dimensions

For maximum efficiency, the OCV control valve should be mounted in a piping system so that the valve bonnet (cover) is in the top position. Other positions are acceptable but may not allow the valve to function to its fullest and safest potential. In particular, please consult the factory before installing 8″ and larger valves, or any valves with a limit switch, in positions other than described. Space should be taken into consideration when mounting valves and their pilot systems.

A routine inspection & maintenance program should be established and conducted yearly by a qualified technician. Consult our factory @ 1-888-628-8258 for parts and service.