Spark During The Control Relay Turn Off

I used omron MY2N control relays to drive the DC24V current to turn on/off the hydraulic valves. I found that the spark will occur between the contact during turned off the control relay. Is there any countermeasure for me to dissipate the spark? Thanks

Star Delta Starting For Pump Which More Than 3.7kw?

Dear all,

Can I apply the direct on starting to Grundfos pump which in AC380, 7.5 kw? As i know, for those motor which more than 4HP need to use the star delta starting to reduce the inrush current. But, i find out that many japanese industrial washing machine didn't apply the star delta starting for those pump which in 7.5 kw. It is OK? It is the inrush current for pump in 7.5kw is lower if compare to general motor which in 7.5 kw??

Circuit Protection

Hi All,

I'm trying to design a circuit for a conveyor system. During the circuit design i was confused for selecting the protection devices for my single phase 220vac equipment (Example PLC, Power supply). What's the different between circuit protector (Example: Fuji)and molded case circuit breaker(Example: Fuji)? And, what's the different for 1 pole circuit protector and 2 poles circuit protector within a electrical circuit?