Application of Signal Isolator in Water Treatment Control System

“Within the water remedy management system, the non-electricity analog sensor of its management and monitoring module adopts the wiring technique of sign isolator to moderately clear up the issue of the security and relative independence of the facility provide of the associated analog sensor, and make sure the energy provide and analog amount of the monitoring module. The relative isolation of the acquisition module and the output module reduces the likelihood that the template could also be burned and broken, improves the measurement accuracy of the analog sign and the anti-electromagnetic interference functionality, and in addition solves the limitation of some on-site non-electrical set up situations.

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Ankerui Zhong Xiaodong

0 Overview

Within the water remedy monitoring automation system, some analog alerts should be monitored, together with electrical analog alerts (resembling present, voltage, energy, and so forth.) and non-electrical analog alerts (resembling stress, water stage, circulate, and so forth.). The ability analog sign is offered by the transmitter, which might usually output an remoted 4-20mA sign, with out the necessity for an exterior sign isolator. The working energy provide of non-electricity analog sign sensors is mostly taken from the DC24V energy provide module offered by the automation system tools, and most of them aren't remoted. As a way to notice the security, stability and relative independence of the facility provide of the analog sensors associated to every management and monitoring module, cut back the likelihood of breakdown or burning of the facility provide module because of the exterior brief circuit of the working energy provide circuit of a sure analog sensor, and endanger the operation security of the automation system of the associated tools. , particularly for these analog sensors that must implement out-of-limit alarm, motion shutdown and vital tools out of operation in course of management, it's a helpful alternative to make use of sign isolators, in any other case it might trigger misoperation, which isn't conducive to the security of all the system. Secure operation, and even trigger pointless losses.

1 Analog sensor wiring technique kind

Within the water remedy automation management system, it's usually essential to measure and monitor non-electrical alerts resembling stress, water stage, and circulate on web site. Stress sensors, water stage sensors, and circulate sensors are sometimes used. These non-electrical sensors are divided into 2-wire and 3-wire. As a way to guarantee the security of the facility provide, DC24V is mostly used, and the generally used technique is to make use of the DC24V energy provide offered by the related management system tools. There are numerous sensors to be monitored in all the water remedy automation management system. Take note of their significance and make sure the security of the on-site management unit. Usually, an unbiased DC24V energy provide module is offered. As a bridge connecting the sensor and PLC, the sign isolator not solely improves the analog sign measurement accuracy, anti-electromagnetic interference potential, and electrical isolation security efficiency, but in addition can moderately clear up the issue of the security and relative independence of the sensor energy provide.

The 2-wire system transmits DC4-20mA normal alerts whereas supplying energy with two wires; the three-wire system makes use of one line for the constructive finish of the facility provide, one line for the constructive finish of the sign output, and one line for the unfavorable finish of the facility provide and the unfavorable finish of the sign. The voltage reference level and the present loop are principally powered by DC24V, and the output sign has a regular DC4-20mA sign; the four-wire system signifies that the facility provide loop and the sign loop are unbiased, separated by an isolation circuit, two wires are answerable for the facility provide, and the opposite two Traces are answerable for outputting alerts (resembling voltage, present, and so forth.).

1.1 Utility of sign isolator in analog sensor wiring

Cheap isolation measures aren't adopted for the working energy provide of the sensor and the analog sign enter, which can trigger hurt: When the cable or the sensor area connector is short-circuited, or the sensor put in open air is struck by lightning overvoltage, it's going to endanger the management and monitoring system on-Screen energy provide The protected operation of the module and the analog acquisition module might trigger the template to interrupt down or burn, which can significantly have an effect on the operation of the management and monitoring system. On the similar time, for 2-wire, 3-wire and 4-wire sensors, the facility provide and sign aren't moderately remoted, and their measurement accuracy and anti-power frequency electromagnetic interference potential are tremendously diminished, and their measurement accuracy and anti-interference potential may even be affected. In recent times, many giant and medium-sized water remedy programs in China have adopted the wiring technique of sign isolators within the energy provide and sign circuit of non-electrical analog sensors to resolve and keep away from the above issues.

2 BM100 sign isolator

2.1 Overview

BM100 sequence sign isolators are utilized in industrial manufacturing to extend the load capability of the instrument and be sure that the devices linked to the identical sign don't intrude with one another, and enhance {the electrical} security efficiency. The BM100 sign isolator enter helps three enter modes, suitable with three wiring strategies of the sensor, isolates the enter sign for output, and safely transmits it to the secondary instrument or PLC/DCS.

2.2 Technical parameters

2.3 Utility Examples

As a result of limitation of the set up situations of the non-electricity sensor on the water remedy web site of a sure group, its analog output sign must be expanded to resolve the issue that one channel of 4~20mA analog sign is concurrently transmitted to 2 units of various management and monitoring programs. It belongs to the two-wire system and desires to supply an remoted energy provide for the sensor on web site. The only-channel DC4-20mA analog amount expands the dual-channel DC4-20mA output sign, which realizes the relative independence of the water remedy management and monitoring system. This technique has excessive isolation energy, robust load capability, easy set up and wiring, steady operation, security and reliability, and on the similar time solves the issues brought on by the set up of sensors on the water remedy web site.

3 Conclusion

The above non-electricity analog sensors undertake the wiring technique of sign isolators, which have been utilized within the water remedy automation system and have achieved good outcomes. At current, they've been utilized within the water remedy of a sure group, which has performed a great function in enhancing the automated management and monitoring stage of water remedy. Demonstration.

references

[1]Enterprise Microgrid Design and Utility Handbook. 2020.6.
[2]Liu Shuqin[1]Dang Qi[2].Utility of monitoring system in automation system of hydropower station[J].China Science and Expertise Expo, 2012(11):102-102.