Testing A Generator
- Thread starter fulham sparks
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erm... the earth rod does not make it TT. a genny that size will be TNS. you then take your L(s),N & E from the genny to installation.
the rod is there for the same reason a DNO transformer has an earth rod... to provide a return earth path back to star point...
for any Z testing, the earth rod at the genny MUST be connected
the rod is there for the same reason a DNO transformer has an earth rod... to provide a return earth path back to star point...
for any Z testing, the earth rod at the genny MUST be connected
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he is testing Zs at the genny,
why wouldnt it be TT then Andy?
you are not permitted to use TN on a private installation if you are working to 7671
why wouldnt it be TT then Andy?
you are not permitted to use TN on a private installation if you are working to 7671
you can use TN on a private installation and work to 7671.... you cannot use TNC
it would only be TT if there was an earth rod at the genny, then another rod at the installation, with no earth connection to the genny
really, the situation is almost identical to a normal TNS supply, except that the supply is by a genny and not DNO
only ZS test you can do at the genny is between any phase and earth terminals
but you dont TT them. you add an earth rod simply as a return path. the cable you use to conenct the installation to the genny will have an earth in it which is connected to the earth at the genny. you have a TNS system
you will only ever get a TT system from a genny if you install a rod at the genny, then at the installation you drop the earth conenction from the genny and install a rod (like you would do if you were to TT a shed).
some smaller 'site' gennys are usually IT although can also be TNS
yes, never connect the earth from genny to supply head [as such],
only use the earth to protect the supply cable,
i dont think gennys should ever be anything other than TT,
but, thats just a preference of mine.
generally the situations where gennys are used are more prone to damage to cables than normal.
only use the earth to protect the supply cable,
i dont think gennys should ever be anything other than TT,
but, thats just a preference of mine.
generally the situations where gennys are used are more prone to damage to cables than normal.
