Control Devices

Model: 7970HA

The model 7970 pressure sensor is a heavy duty pneumatic or hydraulically controlled switch that can sense pressures ranging from 10 to 10,000 psig - in 1 switch, no extra parts or different springs are needed. This is accomplished by dividing the sensing pressure field into four ranges via a brilliantly designed variable area sensing piston.

Four piston configuration ranges:
-10-290psig (68.95kPa-2000kPa)
-290-1440psig (2000kPa-9929kPa)
-1440-5900psig (9929kPa-40.68MPa)
-5900-10,000psig (40.68MPa-68.95MPa)
Changing the piston arrangement is accomplished by simple re-arrangement of the piston parts installed, plus those found in the onboard parts tube located in the center of the sensing spring.

All this and a deadband of only 3-4% of setpoint and industry leading economics of ownership.

Design Features:

Dimensions: 1.750” Dia. X 8.000” L.
Working Pressure: Sensed Inlet - 10 - 10,000 PSIMax.
Process Connections: 1/2”-14 MNPT & 1/8”-27 FNPT
Control Connections: 1/4”-18 FNPT
Weight: 3.5 lbs.
Panel Mount Detail: 1 5/8” diameter hole required.

NOTE:
A. Instrument Supply pressure 30-125 PSI Pneumatic or Hydraulic.
B. Extra parts for changing piston arrangements are stored in tube in adjusting cap.

Other 7970 Series Models available:

7970-20M - 2,000-20,000 PSI Adjustment Range with 9/16 Medium Pressure Conn
7970-20H - 2,000-20,000 PSI Adjustment Range with 9/16 High Pressure Conn
7970T - Teflon “wetted” O-rings, NACE Certified
7970LP - Low Pressure, 2-50 PSI adjustment range
7970H-A - Offset instrument controls ports for 3/8 tubing
7970SS - All stainless steel (316SS)
7970DSS - Duplex stainless steel “wetted” parts

For piston re-configuring and re-ranging instructions watch the video linked above.

Model: HLR5000

HLR Controls has taken a 7970 Pressure Sensor set (PSHL)(The PSHL is the automatic reset hi and low set), and an HLR 150-14FM Manual Reset Relay (MRR) and tubed it up in a typical single well hook-up configuration to allow for sensing and tripping of both hi and low pressure setpoints with start-up bypass and with monitoring of control circuit pressure all encased in a full 316SST package.

Model: 7970SETLPRA

The economical Single well safety system with a manual bypass of low pressure switch for start-up. Once a safe minimum operating pressure is met then the low sewtpoint bypass clears to allow all shutdowns to activate on trip, of either hi or low pressure.