Turck safety barrier

Turck safety barrierIM21-14-CDTRI
Turck safety barrier, connected between intrinsic safety circuits and non intrinsic safety circuits. Supply essential safety
A device that limits the voltage or current of the entire circuit within a certain safe range.

Safety barriers, also known as safety limiters, are an important component of intrinsic safety systems.
There are two main types of safety barriers: Zener safety barriers and isolation safety barriers.
The core components of a Zener safety barrier are Zener diodes, current limiting resistors, and fast melting wires.
Isolation type safety barriers not only have limited energy functions, but also isolation functions. They are mainly composed of circuit energy limiting units, signal and power isolation
Composed of units and signal processing units.
The main function of a safety barrier is to limit current and voltage, ensuring that the energy available to on-site instruments is within a safe range.

Safety barriers, also known as safety retainers. The safety interface of the intrinsic safety circuit can be located in both the safety zone (intrinsic safety) and the danger zone（
Non intrinsic safety) can transmit electrical signals in both directions and limit the transfer of energy from safe areas to hazardous areas caused by faults. one

Generally, safety barriers come in both Zener and isolation types[1].
The intrinsic safety barrier is applied in the design of intrinsic safety explosion-proof systems. It is installed in a safe place and contains intrinsic safety circuits and non essential components
The device of intrinsic safety circuit restricts the energy sent to the on-site intrinsic safety circuit through current and voltage limiting circuits, thereby preventing non essential components
The hazardous energy of the intrinsic safety circuit enters the intrinsic safety circuit, which is called associated equipment in the intrinsic safety explosion-proof system and is an important part of the intrinsic safety system
component.
Intrinsic safety explosion-proof system associated equipment refers to devices installed in safe places between intrinsic safety electrical equipment and non intrinsic safety electrical equipment
Connected electrical equipment.
Due to the safety barrier being designed as an energy limiting interface between on-site equipment and control room equipment, regardless of
The control room equipment is in normal or faulty state, and the safety barrier can ensure that the energy transmitted to the on-site equipment through it is inherently safe
of
The China National Instrument and Meter Explosion proof Safety Supervision Station is responsible for supervising the production of safety and explosion-proof products in the People's Republic of China. It has strict, scientific, and detailed regulations for intrinsically safe safety barrier products. Only enterprises certified by this supervision station and
The products developed and produced by it must have safety performance that meets the standards, otherwise it may affect the equipment, personnel, and production of the user
Causing incalculable damage.

（safety barrier）， Connected between intrinsic safety circuits and non intrinsic safety circuits. Supply essential safety
A device that limits the voltage or current of the entire circuit within a certain safe range.

Exia IIC
Fast fuses, current limiting resistors, or voltage limiting diodes are used in the circuit to limit the input electrical energy, thereby ensuring
Energy output to the danger zone.
1． The installation location must have a very reliable grounding system, which is obviously a very demanding requirement and has practical engineering applications
It is difficult to guarantee.
2． Zener safety barriers have a significant impact on the power supply and are also prone to damage due to fluctuations in the power supply.
3Due to the circuit principle of the Zener safety barrier requiring absorption of energy from the input circuit, it is prone to output instability.

Isolated safety barrier

Adopting a circuit structure that electrically isolates the input, output, and power supply from each other, while complying with intrinsic safety restrictions
Energy requirements. Compared with Zener safety, although it is more expensive, its outstanding performance advantages bring benefits to user applications
Greater benefits have been gained:
1Due to the use of a three party isolation method, there is no need for a system grounding line, which greatly facilitates design and on-site construction.
2The requirements for instruments in hazardous areas have been significantly reduced, and there is no need to use isolated instruments on site.
3Due to the fact that signal lines do not require a common ground, the stability and anti-interference ability of detection and control circuit signals are greatly enhanced
And it has improved the reliability of the entire system.
4Isolated safety barriers have stronger input signal processing capabilities and can accept and process thermocouples, thermistors, frequencies, etc
Signal, this is something that Zener safety barriers cannot achieve.
5The isolated safety barrier can output two mutually isolated signals to be provided to two devices using the same signal source,
And ensure that the signals of the two devices do not interfere with each other, while improving the electrical safety insulation performance between the connected devices.
Therefore, after comparing the characteristics and performance of Zener and isolated safety barriers, it can be seen that isolated safety barriers have outstanding advantages
And for a wider range of uses, although its price is slightly higher than that of Zener safety barriers, it incurs design, construction, installation, commissioning, and maintenance costs
Considering this, its overall cost may actually be lower than that of a Zener safety barrier. Almost without exception, high demand engineering sites adopt
Isolated safety barriers have been used as the main intrinsically safe explosion-proof instruments, gradually replacing Zener safety barriers
The field of full explosion-proof has been increasingly widely applied.
Definition of intrinsic safety equipment labeling
among whichEX —Explosion-proof marking
（ia）—Explosion-proof rating
ⅡC —Gas group
Our company's product explosion-proof level:EX（ia）ⅡC


① Compared with Zener safety barriers, although the price is higher, there are still many advantages and features of isolated safety barriers
Users bring a lot of convenience, which makes more and more users prefer to choose isolated safety barriers.
②The use of isolated safety barriers can effectively isolate the on-site circuit signals in hazardous areas from the circuit signals in safe areas. This is intrinsic safety
The self-control system does not require an intrinsic safety grounding system, simplifying the construction of intrinsic safety explosion-proof systems.
③ The use of isolated safety barriers greatly enhances the anti-interference ability of detection and control circuits, and improves system reliability.
④Use isolated safety barriers, allow field instruments to be grounded, and allow field instruments to be non isolated.
⑤ The isolated safety barrier has many protective circuits, and the possibility of accidental damage is relatively small, allowing on-site instrument maintenance with power on,
This can shorten the preparation time for engineering driving and reduce parking time.
⑥Isolated safety barriers have strong signal processing capabilities. Such as switch input state controlmVThePt100change into4～20mAwait
Wait. This provides greater convenience, rationality, and effectiveness for the application of on-site instruments and control systems.
⑦ When users apply simultaneouslyDCSandESDWhen using a one in two out safety barrier, it can effectively isolate the two systems
To avoid mutual influence between systems.
⑧Circuit powered isolated safety barriers not only maintain the advantages of active isolated safety barriers, but also have the same wiring configuration as Zener safety barriers
Okay, there's no need for anything else24VPower supply, especially suitable for matchingI/OCard powered directlyDCSSystem.

（safety barrier）， Connected between intrinsic safety circuits and non intrinsic safety circuits. Supply essential safety
A device that limits the voltage or current of the entire circuit within a certain safe range.