Testing The Ems Soft Starters

[marke]

Although the EMS soft starter is getting very old, there are still many giving good service in industry.

 

To check the performance of the starter, I always begin by connecting three phase on input and three 300 Watt star connected lamps on the output, star connected with the star point isolated from other circuitry. i.e. a three wire circuit.

 

All three lamps should ramp up evenly to full brightness.

Using a multimeter, ensure that there is full line voltage across each lamp.

Because there is the potential for one SCR to be lazy, measure the voltage forward and reverse.

 

Best regards,

Mark.

[jOmega]

Additional considerations:

 

1. For Safety Reason......Each leg should be fused with fast acting fuses.
   
2. For Safety Reason..... Light bulbs should be enclosed by a wire mesh screen.
   Bulbs can and will explode when least expected.
   
3. Use 300-watt bulbs as Mark stated.
   If you use bulbs of lower wattage, you may not draw sufficient current to satisfy
   the I_h (Holding Current parameter) of the SCR's, and they will turn-off.
4. Strip heater elements could be used instead of light bulbs. Just be sure that they are rated correctly for voltage and minimum wattage required.
   

Kind regards,