Fingers crossed it'll cut ally

**blackburn mark** · 22-12-2010

iv now got a problem with my machine tripping the power
iv got 1 12v power supply 1 24v power supply and one pc power supply
they all work fine when i wire them up individualy
when installed together in my machine more often than not when i hit the on switch everything tripps

a mate of mine said i may have an earth leak (somthing to do with the diffrent power supplies interacting) and the breaker is seeing this as a fault
has anyone any ideas how i might get around this ????

**Jonathan** · 22-12-2010

Could it be the initial surge when you switch it on? Can you switch each power supply on individually? The lights in my workshop dim briefly when I switch my steppers on.

**blackburn mark** · 22-12-2010

i was hoping id missed somthing simple... ill give that a try jonathan
its really holding the job up now and i want to get started cutting things to bits :)

**FatFreddie** · 22-12-2010

Is it a current trip or an earth leakage one?

**blackburn mark** · 22-12-2010

Is it a current trip or an earth leakage one?

i cant be 100% sure i share a house with ten other people and the breaker is in somone elses part of the house (i dont want them sussing it me that keeps blowing the power ill get the shit kicked out of me :)

im pretty sure its an earth leak because of the three switching power supplies (all of them will be leaking a bit i guess)
i was thinking ill get a cumalative spike as they all come on at the same time

i have had the thing running and all seems well, it only trips when i power up

**FatFreddie** · 22-12-2010

Hmm, separating the switch on times sounds your best bet then - at least it's a fairly easy one to try.

You could try putting a lower current rating RCD and or breaker between it and the fuse board to reduce your chances of injury (flat mate induced, not electrical) but I suppose they'd need to be faster reacting to be sure they tripped in advance of the main one...

**blackburn mark** · 22-12-2010

flat mate induced

hahha!!
yep, id give it a go if a knew it would trip before the main one
i need to take it off the surge protector as well, iv read they leak as well

**m_c** · 23-12-2010

Are switching live and neutral, or just live?

I know that VFD's are prone to tripping RCDs if you switch both on at the same time, and given that VFDs are basically a very fancy switch mode power supply...

**Jonathan** · 23-12-2010

Originally Posted by m_c

Are switching live and neutral, or just live?

I know that VFD's are prone to tripping RCDs if you switch both on at the same time, and given that VFDs are basically a very fancy switch mode power supply...

Slightly off topic but that reminds me...my router had a switch in it which switched both live and neutral. Is it safe to connect the neutral permanently and have the live on a relay (solid state)?

**templecorran** · 23-12-2010

If you think about it ... the mains plug only switches the live, the neutral is unswitched. you can happily feed through the relay. Solid State relays are prone to not switching off though. I use a 4PDT relay with all 4 poles switching the current. I was concerned with the inductive load of the router causing contact burn with just one pole. my 1020W motor is capable of drawing over 4 amps on load, I lacked confidence that my relay contacts were up to that :-)