- Thread starter Coo
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Coo
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They don't necessarily need earthed...they have a floating earth and as such are wired differently than the mains...
Thats the reason you need a different RCD..although you can use a normal RCD if you mod the generator wiring...and use an earth spike...
I'll look into the mechanical RCD
Thats the reason you need a different RCD..although you can use a normal RCD if you mod the generator wiring...and use an earth spike...
I'll look into the mechanical RCD
the snooper
getting older by the day
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yes i see your point.
removed my op as yours made sence
removed my op as yours made sence
brightspark
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that is corect it involves linking the neutral on genny to the chasis earth then it needs the rcd with an earth rod
all the larger fixed standby generators are neutral to earth linked and require all circuits to be through an rcd with earth rod . an rcd device works by leakage to earth by either the live or the neutral causing current imbalance which operates the switch
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madkayaker
Pro sparkey Pro Welder
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there supposed to be earthed if you are using more than one item of equipment on them and for more that one shift (site rules from wiring regs)
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I will have to check if the neutral & earth are linked internally, genny does have an earth connection for ground spike.
Thanks for info on mechanical RCD's.
Going to use it to power about 8-10 lights & a couple of socket outlets.
Thanks for info on mechanical RCD's.
Going to use it to power about 8-10 lights & a couple of socket outlets.
Hello Brightspark,
"an rcd device works by leakage to earth"
that is a misleading statement. Many years ago that was true but now it is current imbalance between live and neutral (as your drawing with the ct shows). The arrow on the earth return is misleading in describing the operation of the equipment.
The idea of also fitting an earth spike is not really helpful bearing in mind the uses portable generators are put to in the context of what most people here use them for.
Alec
"an rcd device works by leakage to earth"
that is a misleading statement. Many years ago that was true but now it is current imbalance between live and neutral (as your drawing with the ct shows). The arrow on the earth return is misleading in describing the operation of the equipment.
The idea of also fitting an earth spike is not really helpful bearing in mind the uses portable generators are put to in the context of what most people here use them for.
Alec
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Surely the only way you could get a current imbalance is to earth? the only other choice is a fault between live & neutral bringing both lines to same potential so no imbalance.
Hello Robotstar.
yes that is right but the description of what senses the imbalance is what I was trying to clarify. The old earth leakage trips did just that by sensing earth fault current. Incidentally it will also work on a three phase system without a neutral if all phases are monitored.
Alec
yes that is right but the description of what senses the imbalance is what I was trying to clarify. The old earth leakage trips did just that by sensing earth fault current. Incidentally it will also work on a three phase system without a neutral if all phases are monitored.
Alec
brightspark
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the current between live and neutral is a balanced load .if there is any leakage to earth on either live or neutral conductor that gives the current imbalance which trips the circuit. just to clear it up . as i said in earlier thread standby generators are neutral to earth linked requiring the earth rod . a small portable generator has no need for one. or the rcd
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No worries, I see what you meant now.
Been reading up recently on RCD, RCBO, RCCB etc recently to provide protection on a inverter drive, the manual likes to call it a GFI (guess where it was written!).
brightspark
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the old trips were voltage operated line to earth faults the new ones are curent operated
