Why Electrical Box required Digital Voltage protection relay

Why Electrical Box required Digital Voltage protection relay



            Under – Over Voltage is a common problem in the industrial manufactory, Building, Accommodation. Although the under voltage or over voltage in a short time it affects to the fault in operating and in case of the electrical has a problem or interrupted. If there are not high-quality protection devices that can lead to damage to the electrical equipment, production line, building or office, etc. Especially, the cause of danger from the device explosion that harms the staff around the install area.

The fault in the electrical as follow by:

  • Short Circuit
  • Overload
  • Surge
  • Over Voltage
  • Under Voltage
  • Phase Unbalance
  • Phase loss
  • Phase Sequence

                     Electrical Warning Sign


            High-quality protections are necessary for the industrial. Today, we will introduce the electrical protection or the engineer well know device name Protection relay or Phase Protection Relay which has a rotary range selector (Model PM-017) by Set Point percentage of Over – Under Voltage. The phase protection shows the status and the electrical fault through the LED.          

If we need to know the true value of voltage without the calculation about a percent voltage for using the electrical box, control box and Main Distribution Board etc. with Under – Over Protection and Digital Phase Protection Relay or Digital Voltage Protection Relay. We will introduce in the topic Why Electrical Box required Digital Voltage Protection Relay” by  Digital Voltage Protection Relay is the electrical fault detector  and cut off the problem from distribution source immediately such as Over Voltage, Under Voltage, Phase loss, Phase Sequence for protect the equipment from damage. For example, Digital Voltage Protection Relay Model VPM-05 why it has been installed in the electrical box (Picture A).


The Display of  Digital Voltage Protection Relay Model “Primus” VPM-05



Digital Voltage Protection Relay Model VPM-05 is the Digital Under – Over and Phase loss protector device. It comes with the 7 Segment in Red light and shows the voltage. Font Alphabets and Number size 0.39 inches for supporting the vision. The LEDs show the status of the Alarm report when the system has a problem.  

Digital Voltage Protection Relay CAN protect the basic electrical system problem according to by the standard industrial manufactories that we found in regularly as follow :



Digital Voltage Protection Relay able to select the connection to 1 phase or 3 phase system



Wiring Diagram of  Digital Voltage Protection Relay Model VPM-05with motor

The advantages of Digital Voltage Protection Relay

  1. Protect the devices like Motor, Inverter, Switch Mode Power Supplies, Computer, Packaging Machine, etc. from electrical fault such as Over-Voltage, Under-Voltage, Phase loss, Phase Sequence.
  2. Status Alarm warning when the system has a problem immediately for Technician, Engineer to verify and maintenance easily.
  3. The Display inside. Save cost and not require Meter for Monitor.
  4. Available for programing the function easily and not require the calculation.


Pictures show Digital Voltage Protection Relayin the platform