Electronic Actuated Pressure Sustaining Control Valve

Product Advantages

  • Simplified Remote Valve Set-Point Control
  • Ideal for use with VC-22D Electronic Valve Controller
  • 12 to 24 VDC Input Power
  • Isolated Input
  • Reverse Polarity Protection
  • Reliable Hydraulic Operation
  • IP-68 (Submersible)

The Cla-Val Model 350-07 Electronic Actuated Pressure Sustaining Control Valve with Manual Hydraulic Bypass combines precise control of field proven Cla-Val hydraulic pilots and simple, remote valve control. The Model 350-07 is a hydraulically operated, pilot controlled, modulating valve designed to maintain constant upstream pressure within close limits.

This valve can be used for pressure sustaining, back pressure or unloading functions in a by-pass system. The valve uses a CRL-34 pilot control, consisting of a hydraulic pilot and integral controller, that accepts a remote setpoint command input and makes set-point adjustments to the pilot.

The recommended control method is simple remote set point change from an RTU (Remote Telemetry Unit) to the CRL-34 where the 4-20 mA command signal is ranged to specific pressure range. Very accurate control can be achieved when span does not exceed 100 psi. Since the CRL-34 is pre ranged to the full spring range,some on-site calibration may be necessarywhen this control method is used. Free downloadable software is available from the Cla-Val website for this purpose. The CRL-34 can also accommodate control systems where the RTU compares pressure transmitter signal to the remote set point command signal. The RTU adjusts the CRL-34 with 4-20 mA command signal containing an adequate deadband to prevent actua tor dithering after the two signals agree. Internal continuous electronic monitoring of actuator position results in virtually instantaneous position change with no backlash or dithering when control signal is changed. In the event of a power or control input failure, the CRL-34 pilot remains in hydraulic control virtually assuring system stability under changing conditions. If check feature (“D”) is added, and pressure reversal occurs, the valve closes to prevent return flow. During SCADA startup and maintenance, the manually-adjusted CRL pilot control allows automatic hydraulic valve operation when no electric power is available for CRL-34

Schematic Diagram
Item Description
1 Hytrol Main Valve 100-01
2 X58C Restriction Fitting
3 CRL-34 Electronic Pressure Sustaining Control
4 CRL5A Pressure Relief Control
5 CK2 Isolation Valve

Optional Features
Item Description
A X46A Flow Clean Strainer
B CK2 Isolation Valve
C CV Flow Control (Closing)
D Check Valves with Cock
H Drain to Atmosphere
P X141 Pressure Gauge
S CV Flow Control (Opening)
V X101 Valve Position Indicator
Y X43 Y Strainer

The valve is designed to be used with supervisory control systems (SCADA), having remote analog set-point output and process variable upstream pressure input. It is also an effective solution for lowering costs associated with “confined space” requirements by eliminating need for entry into valve structure for setpoint adjustment. Additional pilot controls, hydraulic and/or electronic, can be easily added to perform multiple control functions to fit exact system requirements

Model 350-07 (Uses Main Valve Model 100-01)

Pressure Ratings (Recommended Maximum Pressure – psi)


Model 350-07 Dimensions (inches)

Model 350-07 Metric Dimensions (Uses Main Valve Model 100-01)

CRL-34 Overview

The Model CRL-34 Electronic Actuated Pressure Sustaining Pilot Control provides remote set-point adjustment and accurate upstream pressure control on Cla-Val 350 Series Electronic Control Valves. Remote set-point command signals can be sent from Cla-Val’s VC-22D e-Controller or any SCADA-type control system using an analog 4-20 mA signal, by contact closure for counter-clockwise / clockwise rotation or through Modbus RTU.

The CRL-34 senses valve inlet pressure directly. Operating on 12 to 24 VDC and consuming very little power, they are an ideal control system for remote valve sites that may even be solar-powered.Existing manually set Cla-Val 50 Series Pressure Relief/ Pressure Sustaining Control valves can be retrofitted with CRL-34 pilots to add remote set-point control of upstream pressure. Verification of minimal upstream pressure may be sent to SCADA systems from customer supplied pressure sensors attached to the valve inlet.

CRL-34 Subassembly Specifications

Adjustment Ranges
0 to 75 psi
20 to 105 psi
20 to 145 psi

End Connection
1/2″ and 3/4″ Threaded

Temperature Range
Water: to 176°F / 80°C

Pilot Control: Low Lead Bronze
Trim: Stainless Steel Type 303
Rubber: Buna-N® Synthetic Rubber

Available with optional Stainless Steel or Monel materials at additional cost. Consult factory for details.

Note: Total Shipping Weight: 8 Lbs.

When Ordering, Please Specify
1. Catalog No. 350-07
2. Valve Size
3. Pattern – Globe or Angle
4. Pressure Class
5. Threaded or Flanged Installed
6. Trim Material
7. Adjustment Range
8. Desired Options
9. When Vertically

CRL-34 Actuator Specifications

Supply Power Input:
12 to 24 VDC
No Load draw: 50 mA
Max. Load draw: 250 mA

Remote Command Inputs:
• 4-20mA, analog signal (isolated and reverse-polarity
• Dry contact closure (CW/CCW)

Position Feedback Signal:
4-20 mA

Alarm Output:
Dry-contact closure (High/Low)
Speed of Rotation: Adjustable On/Off time, max 6 rpm

LED Indicator

Loss of Power:
Actuator will remain in last commanded

Loss of Signal Position:
Programmable – 4 mA, Last, or 20 mA

Electrical Connections:
Single, 30 feet of permanently attached cable with color-coded power supply and signal wires

Mechanical Specifications:
Protection Class: IP-68 (Temporary submersible)
Ambient Temperature: 15° to 150° F (-10° to 65° C)

Electronic Enclosure: Anodized Aluminum
Mechanical Housing: Bronze
Coupling Assembly: Stainless Steel
Gear Train: Stainless Steel, permanently lubricated