• Low Pressure High Flow Proportional Regulator(0-8bar)
Low Pressure High Flow Proportional Regulator(0-8bar)
Product Serial: QKL-B1H

Low Pressure High Flow Digital Pressure Regulator (0-8bar, 116 psig)
Digital pressure regulator is a type of air pressure regulator where the output air pressure is proportional to the input electronic signal. QKL-B1H series digital pressure regulator features high flow rate at general air pressure application. It has a construct of two solenoid valves, one internal pressure transducer, intelligent electronics, and an internal volume booster. It is ideal for either static or dynamic large flow rate application. The output pressure of QKL-B1H digital pressure regulator is 0.1% error linearly proportional to the input command signal.

Features and Applications
QKL-B1H digital air pressure regulator features a flow rate of 5600 L/min at 116 psig (8 bar) inlet pressure. It provides high performance features in case of downstream high volume container or a high dynamic flow environment, such as blow moulding, or spraying application. Having an accuracy of 0.3% F.S., customers have also used this regulator to directly regulate a 100 L container in semi-conductor equipment and industrial equipment.

This series provides industrial leading ultra-high flow digital air pressure regulator instead of using an external volume booster, thus that customers save mechanical space in the working machines/process.

Working Principle
An electronic air regulator consists of one pressure transducer, one valve responsible for air intake, one valve responsible for air exhaust, intelligent electronics, and one internal volume booster. The volume booster is indirectly driven the either valves to increase or decrease the output flow of air. When an electronic signal is given, one valve opens to allow air inlet, which indirectly expands the space in the volume booster. As soon as the pressure sensor senses that the output air pressure exceeds the set signal, the other valve opens to exhaust internal air, which results in the closure of the volume booster.

A high frequency control and movement of the valve allows one to regulate the output pressure in fast and high accuracy manner. The input electronic signal can be 0-10V, 4-20mA, or RS485-modbus. Other customized analogue signal is also possible. The output pressure can also be monitored by reading the output cable in the regulator.

This digital pressure regulator consists of a volume booster, whereas other series such as QKL-B1S and QKL-B1T does not have volume booster. Comparison of two types of regulators is listed below:




  QKL-B1S / - B1T

Flow Rate



Dynamic Working Condition


Very limited flow rate

High Resolution Control






Susceptible to dirt particles



Table 1 showing the comparison between QKL-B1H and QKL-B1T digital pressure regulator

1. What fluid type can be used?
A. Dry, compressed air, inert gas, oxygen gas (on request). Filter of 40 um required.

2. How many regulators in serial can be controlled with RS485-Modbus?
A. We have set 15 addresses in our serial communication.

3. The regulator becomes warm when operating, what is the reason for this?
A. The regulator consists of 2 solenoid valves. When the set pressure cannot be reached, the valves continuously to work in attempt to reach target pressure. There are several reasons that the valves continuously, such as inlet pressure lower than the set input signal, dirt particles stuck in the air pathway…etc.

4. In case a lower volume of flow is needed, what type of electronic air regulator can be used?
A. You can choose either QKL-B1T, refer to this webpage.

◆ Compact
◆ High Precision
◆ High Sensitivity
◆ Fast Response Time
◆ Ultra-High Resolution 0.01 psig
◆ Ultra-High Speed available 100msec

Industrial application
◆ Laser Cutting Machine
◆ Leak Tester
◆ Tension Control
◆ PET bottle molding machine
◆ Multi-Stage Pressure Control
Type B1H
Input Signal 0-10V / 4-20mA / RS485
Output Range 0-8bar (120 psi)
Supply Pressure Max 10 bar (150 psi)
Monitor Output 0-10V / 4-20mA / RS485
Supply DC24V (≦4W)
Response 1S
Medium Clean compressed air or with 5 μm filter
Repeatability ±0.25% F.S.
Hysteresis ±0.25% F.S.
Linearity ±0.25% F.S.
Accuracy ±0.25% F.S.
Sensitive 0.1bar
Flow Rate 5600L/min @ 8bar
Temp. Range(Operating) 0 ~ 70 ⁰C ( 0 ~ 158 ⁰F)
Port Size 1/2"PT
Manifold Material Aluminum
Wetted Materials Aluminum, Stainless steel, NBR
Electrical Connection M12 Connector(2m)
Ingress Protection IP 65
Weight 1600 g