Digital pressure controller, BQJ104



This is an intelligent digital displayed product for pressure testing and controlling. It integrates functions of measuring,display,output and control all in one.It has a complete electronic structure. Oil-filled piezo-restive pressure sensor with diaphragm is applied in the front part. The output is processed by high-precision & low-temperature drift amplifier,then transformed by high accuracy

A/D converter into digital signal that could be processed by MPU(Micro Processor Unit).

The processed signals control two switches then to test&control the pressure.

With flexible application,simple handling,easy debugging and high reliability,this product is widely used applied to test & control the pressure of fluid medium in many industries including areas of hydroelectricity,city water,oil,chemical,machinery hydraulic system etc.


  1. To be stored and used in ambient temperature -20-70℃and relative humility 0-80%,
  2. Connecting thread should be concentric and stable with the pipe system,
  3. When disassemble this product,please do not press it in its body


Pressure range -0.1~0~100Mpa Accuracy 0.5%F.S.
Over load 200% Pressure type Gauge/absolute
Liability ≤0.1% /year Power 24VDC/220VAC
Display 0.56″ LED Display range -1999~9999
Response time <30ms Ambient temperature -20℃~70℃
Relative humidity ≤80% Wetted part SS304


  1. Mechanical connection

It can be directly mounted in the hydraulic pipe by the connecting thread,M20*1.5. In critical application,such as server vibration or shock,soft hose is recommended to use.

  1. Electrical connection

To avoid electromagnetic interference,please know

A.The cable system should be as short as possible

B.To use shielded wire

C.To keep way from any interference resources,for example,electric appliances and devices.If installed by soft hose,its body should be grounded independently.


AL1H: Switch connection point for switch 1(when pressure reaches this value,indicator on)

AL1F: Switch connection point for switch 1(when pressure reaches this value,indicator off)

AL2H: Switch connection point for switch 2(when pressure reaches this value,indicator on)

AL2F: Switch connection point for switch 2(when pressure reaches this value,indicator off)

FILT:Filter coefficient. To avoid digit display from fluctuating which is caused by pressure change.after 3-10seconds,it can be set END then save then exit.The bigger the filter coefficient is,

The more stable it is,but the more hysteric.


Switching points are determined by the configuration of the present connection and disconnection value.

When connection value is higher than disconnection value,it is called upper-limit alarm output(normally open status);

When connection value is lower than disconnection value,it is called lower-limit alarm output(normally close status);

The deviation between connection and disconnection value is the return difference for the switch point.


(How to finish the settings as following)

Set switch point 1 at upper-limit alarm output(normally open status),connect at 4Mpa and disconnection when lower than 3.95Mpa,response delay is 3 seconds

Set switch point 2 at lower-limit alarm output(normally close status),connect at 10Mpa and disconnection when lower than 9.95Mpa,response delay is 10 seconds

Enter the menu:Set

AL1H=4.00  AL1F=3.95

AL2H=9.95  AL2F=10.00

  • Press “SET”
  • “LOCK”sign(remind you to key in password,0001)
  • Press ▲ or ▼ to key in the password
  • Press “SET” to confirm
  • Press ▲ or ▼as page up or page down to select


  • Press “SET” to enter selection menu
  • Press ▲or ▼ to alter the settings
  • Press “SET” to confirm,or press ▲or▼to enter other menus for other settings