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Grizzly
14-11-2016, 06:19 PM
I may have got it wrong!
But are the modern Solenoid coils Double insulated!
Only Most I use, come with an Earth Pin / Terminal.
Does the Earth terminal perform any purpose?
Is it actually necessary?
Thanks Grizzly

chemi-cool
14-11-2016, 06:32 PM
What make are you talking about?

On Danfoss with the "click" connection, its touching the stem of the valve.
Other manufacturers have steel sleeve around the stem which is grounded.

Grizzly
14-11-2016, 06:57 PM
So It's relevant then?
Grizzly

chemi-cool
14-11-2016, 07:15 PM
Earth is always important, it's to save your life!!

There are two common faults with solenoid coils, short winding > will trip control switch. Short circuit between ground and neutral > will trip pcb.

Grounded systems is very important,

HVACRsaurus
15-11-2016, 12:45 AM
Photo shows electrical connection between solenoid earth pin & valve body..14418

Magoo
15-11-2016, 01:36 AM
Hi Grizzly.
had a situation recently with a Sporlan industrial S/V with two wire coil connection and metal casing earthed.
For what ever reason the coil failed , control system C/B tripped and system stopped > Unfortunately the coil failure blew a hole in the solenoid lifting stem. Things got interesting after that, as solenoid was Hp liquid make up valve on ammonia plant. I get called out 6.00am and arrive to WW3, full monty turn out from chemical response team all alarm system worked though and factory cleared. Liquid ammonia pooled on the floor of plant room, stuffed my work boots.

RANGER1
15-11-2016, 07:43 AM
Photo shows electrical connection between solenoid earth pin & valve body..14418i

The old GPLX solenoid to valve body earth trick!

Grizzly
15-11-2016, 08:14 AM
Thanks Guys.
I have never knowingly not connected the earth on any Solenoid Valve.
I just wondered if leaving it off was an option?
My reason was because recently I was involved in replacing the Oil Capacity Solenoid Block on a 4 year old SAB 193. )Sabroe Screw)

Which has now uses a re-designed Block.
With DC coils which has + and - terminals on a pcb within the Din plug. But the earth terminal is below this board on the Terminal Block.
My colleague and I initially questioned whether we could miss out the Earth connection.
However the Earth connections were made despite it being a real pig to do.
But it got me wondering?

Hence the original question.
Thanks Guys!

Ps Magoo I know what you mean about Ruining your boots, been there.
We are issued with Wellington Boots in our "safety Kit!"

Brian_UK
15-11-2016, 10:12 AM
I did read somewhere that if you use the earth terminal in the connector then you shouldn't also put an earth wire onto the earth screw of the valve body if one is fitted.

Sonething to do with potential differences but over my head.....

r.bartlett
16-11-2016, 07:06 AM
Earth is always important, it's to save your life!!

There are two common faults with solenoid coils, short winding > will trip control switch. Short circuit between ground and neutral > will trip pcb.

Grounded systems is very important,
Come live in Tenerife.. E is optional and usually not present :-)

cricri
05-01-2017, 03:38 PM
Hi to all,

coil must be grounded, it's in the Parker instructions.

I have a test report from Parker for those who would like some more explanations

14472

eggs
06-01-2017, 10:34 AM
Come live in Tenerife.. E is optional and usually not present :-)

When I was last in Tenerife E's were obligatory. :cool:;)...old ravers never die.