The Heart of IoT Systems
Monday: February 1, 2021 : Three-Phase Monitor Relays
Protecting Critical Equipment from Voltage Faults
New products that embed communication in phase monitor relays can dramatically change the way equipment is monitored and controlled in smart network control systems. These smart devices give users both control and data connectivity in one device for a fraction of the cost of installing a power monitor.
Phase Monitoring Devices (PMD) protect valuable motors and other three-phase equipment from damage caused by voltage faults. When triggered by a fault in the control circuit, PMD output contacts annunciate or disconnect the equipment.
A technician must physically inspect the phase monitor’s status indicator LED to understand what type of fault occurred. Based on the flashing sequence, the technician can determine the cause of the trip unbalance, overvoltage, undervoltage, phase loss, or phase reversal.
This manual process is effective but not always efficient. The troubleshooting technician must travel to the site of the installation, secure any necessary PPE to open the panel for live visual inspection, inspect the PMD, decipher the flashing sequence to troubleshoot the root cause, record the fault, and close the panel.
Only then can the technician obtain the needed materials to correct the problem.
Communicating with Protection
PC Series PMDs provide the same high level of protection offered on legacy PMDs including local direct control of motor starters. No additional relays or contactors are required.
The PC Series PMDs have separate control power inputs supporting redundant and uninterruptable control power systems for critical applications. Continuous True RMS Sensing provides highly accurate measurement in the most challenging applications.
Adjustable protection thresholds – set locally on the device - allow protection to be customized during the installation without special equipment or software. Fault history records facilitate troubleshooting faults that occur during after-hours or on weekends. Discerning patterns and/or trends is also made easier. Optional local manual reset protects operator safety by preventing unexpected restart of equipment.
An Affordable Alternative to Power Monitors
PC series PMDs provide an economical solution for users wanting a connected control system. These PMDs combine the functionality of phase monitors, voltmeter, frequency meter, and PLC I/O modules in one device.
Simple setting of the protection thresholds using dials on the device eliminates the need for a computer or mobile device at installation. Modbus protocol is open source eliminating any license fees and reducing hardware costs.
Previously, users wanting to communicate phase monitor data on an industrial network required installation of a power monitor, resulting in loss of direct motor starter control and increased costs up to several thousand dollars. The PC Series gives users both motor control and data connectivity for a fraction of the cost.
The PC Series can be connected to an existing HMI to display voltage and fault data locally while simultaneously communicating via the Industrial network to other devices.
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