Principle of work:
First will change delivering or the measuring appliance signal, will modulate the transformation through the semiconductor device, then the transmitted light feeling or the magnetic induction component will carry on the isolation to transform, then will carry on the demodulation to transform before again the isolation the original signal, simultaneously after will isolate the signal electric power supply to carry on isolation processing. After the guarantee transformation signal, the power source, between are absolutely independent.
Function:
One: Protects the subordinate control loop.
Two: Slackens the ambient noise to the test circuit influence.
Three: Suppresses the public earth, the frequency changer, the solenoid valve and the unclear pulse to the equipment disturbance; Meanwhile has the function to the subordinate equipment which the limiting pressure, the volume flows is changes delivering, the measuring appliance, the frequency changer, the solenoid valve PLC/DCS input output and the communication connection faithful protection.
The standard series guide rail structure, is easy to install, but effective isolation: Between input, output and power source and earth electric potential. Can overcome the frequency changer noise and each kind of high low frequency flutter.

Which does the signal disconnector predominant type have?
1) disconnector:
In the industrial production for increases the measuring appliance load capacity and between the guarantee connection identical signal measuring appliance mutually does not disturb, enhances the electrical security performance. After needs the voltage, the electric current or the frequency, the resistance equisignal which inputs carries on gathering, the enlargement, the operation, and carries on antijamming processing, then outputs the isolation the electric current and the voltage signal, safe gives two times of measuring appliances or the plc\dcs uses.
2) distributor:
The industry scene generally needs to use two systems transmission mode, both must for change delivering and so on a measuring appliance to provide the 24V power distribution power source, simultaneously and must carry on gathering, the enlargement, the operation after the input electric current signal, and carries on antijamming processing, then outputs the isolation the electric current and the voltage signal, for behind two measuring appliances or other measuring appliance uses.
3) safety fence:
Some special industry scenes (for example fuel gas company and chemical plant) not only need two systems transmissions, both provides the power distribution power source and to have the signal to isolate the function, meanwhile needs to have the security spark explosion-proof the performance, reliably contains the mains input, prevented between the power source, the signal and the place ignition, limits flows, falls presses the dual clipped wave and the power source return route, enters the dangerous place the energy to limit in the security fixed quantity scope.

Which items does the signal disconnector install the maintenance to be supposed to pay attention to?
Because produces the factory differently, to disconnector production craft, wiring definition not all same, but use situation basic same, therefore requests to the product protection and maintains basically is same.
Before 1. uses should in detail read the instruction booklet.
2. took when signal isolation use, should enter the input end string in the loop circuit, output termination sample return route.
3. took when isolation power distribution use, should merge the input end in the power circuit, the output termination changes delivering.
4. if the normal work should first inspect the wiring is whether correct, whether there is pays attention to the power source and the polarity in any case.

Why sometimes PLC does receive the scene signal error big also the stability is bad?
Creates this kind of phenomenon the reason to be very many, between the different measuring appliance signal reference point potential difference is the important attribute. Because this "the difference" creates between the measuring appliance signal to produce the interference current, causes the PLC error big also the stability is bad. Therefore the different equipment, the measuring appliance signal has a common reference point is the full fine. The disconnector causes on the input/output electricity completely to isolate, meets the oral plate in the PLC simulation to form the common reference point, achieved the ideal condition question solved.

Carries on the isolation to the 4-20mA channel, but in the cabinet has not laid aside the power source the space, how manages?
One kind of passive signal disconnector, it can realize the 4-20mA signal to isolate also not to need the external power supply. PH1033 is this kind of product.

Now the market has that many brand the disconnector, the price is irregular, how should choose?
The disconnector is located between two systems channels, therefore the choice disconnector first must before determine the input output function, simultaneously must cause the disconnector input output pattern (voltage, electric current, ring circuit power supply and so on) to adapt rear end the channel connection pattern. In addition still had the precision □p power loss □p noise □p insulation strength □p main line communication function and so on many important parameters to involve the product performance, for example: Noise and precision related, power loss quantity of heat and reliability related, these need users cautious elect. In brief, is suitable, reliably, the product price compared to is chooses the disconnector the to be main principle.
DCS receives the scene two-wire system pressure changes the delivering signal not to be unstable, how solves?
The two-wire system changes delivering to use the frequency in the industrial automation domain high, is same with other industry scene equipment, the two-wire system changes delivering also to exist is disturbed and the antijamming question. (Electric current or ring circuit power supply) selects the function different isolation distributor based on the DCS simulation board connection pattern, in principle requests it both to be able to give changes delivering to provide isolates the power source, guaranteed each changes delivering to have a independent power supply, and can change the delivering signal isolation to transport DCS.

The PLC simulation board connection is two return routes power supplies way, moreover needs to carry on the isolation to the signal, how should select the product?
Two return routes power supplies way is one kind of common simulation connection. The product suits which with this connection is called the two-wire system return route to isolate the series product. This kind of isolation changes the delivering interior the isolation component to select the transformer method, on the one hand has transmitted the signal, on the other hand also will supply power the end electrical energy to transmit to the input part, will enable the input partial each kind of electric circuit the normal work. Distributor product and so on example PH2217.

How many kind of commonly used two-wire systems distributor has?
The commonly used two-wire system isolation distributor has two series varieties to be allowed to choose. Two series products common ground is can change delivering through exterior electric power supply after the isolation for two systems to provide an independent isolation power source; Changes the delivering power distribution to be decided to the present place matches PLC, the DCS simulation quantity loses.
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