Introduction of some relevant knowledge of isolation safety barrier


Release time:

2022-05-06

Introduction of some relevant knowledge of isolation safety barrier Application Advantages of 1. Selection of Isolation Safety Barrier Compared with Zener safety fence, although the price of isolated safety fence is higher, it still has many advantages and characteristics. The same isolated safety barrier has brought a lot of convenience to users, making more and more users tend to choose isolated safety barrier. Fences require explosion-proof certification and are commonly intrinsically safe.

Introduction of some relevant knowledge of isolation safety barrier

 

Application Advantages of 1. Selection of Isolation Safety Barrier

 

Compared with Zener safety barrier, although the price of isolation safety barrier is higher, it still has many advantages and characteristics. The same isolated safety barrier has brought a lot of convenience to users, making more and more users tend to choose isolated safety barrier. Fences require explosion-proof certification and are commonly intrinsically safe.

隔离安全栅

Characteristics and fault treatment methods of isolation safety barrier:

 

(1) The isolation barrier is used to allow the field instrument to be grounded and allow the field instrument not to be isolated.

 

(2) The isolation barrier can effectively isolate the field loop signal in the hazardous area and the loop signal in the safe area. In this way, the intrinsically safe automatic control system does not need the intrinsically safe grounding system, which simplifies the construction of the intrinsically safe explosion-proof system.

 

(3) The use of isolation barriers greatly enhances the anti-interference ability of the detection and control loop, and improves the reliability of the system.

 

(4) There are many protective circuits for the isolation safety barrier, and the possibility of accidental damage is small. Allowing live maintenance of field instruments can shorten the project start preparation time and reduce the parking time.

 

(5) When the user applies DCS and ESD at the same time, choosing a safety barrier with one entrance and two exits can effectively isolate the two systems and avoid mutual influence.

 

(6) The isolation barrier has strong signal processing capability. Such as switch input state control, mV,Pt100 change 4 ~ 20mA, etc. This provides greater convenience, rationality and effectiveness for the application of field instruments and control systems.

 

(7) The loop-powered isolation safety barrier not only maintains the advantages of the active isolation safety barrier, but also has the same wiring convenience as the Zener safety barrier. It does not require an additional 24V power supply, and is especially suitable for DCS systems directly powered by I/O cards.

 

Treatment Method of Common Faults of 2. Isolation Safety Barrier

 

1. The power indicator does not light up or the LCD screen does not display.

 

(1) Check whether the power connection of the instrument is correct and reliable.

 

(2) Check whether the power supply voltage is normal.

 

(3) Check whether the positive and negative of 24V power supply are reversed.

 

2. No signal output.

 

(1) Whether the input signal is correctly connected to the input terminal.

 

(2) Whether the input signal type is consistent with the instrument input type.

 

(3) Whether the output terminal is fastened.

 

(4) Whether the detachable external terminal is inserted in place.

 

(5) The external output circuit is open.

 

3. The output value deviation is large.

 

(1) Whether the positive and negative leads are connected reversibly when the thermocouple is input.

 

(2) Whether the three-wire connection is correct when the thermal resistance is input.

 

(3) Whether the positive and negative polarities of the output wiring are reversed.

 

(4) When the output current, whether the sum of the external load resistance is greater than the specified ohm (when the output is 4-20mA).

 

(5) When outputting voltage, is the external load resistance less than 500 kilohms.

 

(6) the power supply voltage is too low.

 

4. The output signal is unstable.

 

(1) Check whether the wiring is firm.

 

(2) Check whether the input signal is stable.

 

(3) Check whether the output circuit wiring is reliable.

 

(4) Check whether there is high-power electromagnetic equipment around the instrument.