1. forget "TT". The electrode will be for providing an earth reference or "source electrode" for the generator, which (99.9% of the time) will then form a TN-S system with a N-PE link close to the generator (it can also act as an additional electrode for the grid earth)

Call Pramac and explain, they say put a link in the commando socket that plugs into the generator between N-E.

that sounds like reasonable advise in general - there are some generators that that wouldn't work for though (normally small ones <3kVA intended to run as separated systems).

Do this and generator stalls.

Humm. That might suggest that you're actually shorting L to PE and there's already a link elsewhere .. but that doesn't jive with the lack of an earth loop reading. Some generators that have 115V as well as 230V output actually have two 115V windings and connect the centre point to the frame and 230V is between two lines, rather than line and N .. but you should still get an earth loop, although it would appear to be 115V rather than 230V to earth (which might fool some testers). Maybe some voltage readings L/N, L/PE, PE/N without the link might enlighten.

   - Andy.

1. forget "TT". The electrode will be for providing an earth reference or "source electrode" for the generator, which (99.9% of the time) will then form a TN-S system with a N-PE link close to the generator (it can also act as an additional electrode for the grid earth)

Call Pramac and explain, they say put a link in the commando socket that plugs into the generator between N-E.

that sounds like reasonable advise in general - there are some generators that that wouldn't work for though (normally small ones <3kVA intended to run as separated systems).

Do this and generator stalls.

Humm. That might suggest that you're actually shorting L to PE and there's already a link elsewhere .. but that doesn't jive with the lack of an earth loop reading. Some generators that have 115V as well as 230V output actually have two 115V windings and connect the centre point to the frame and 230V is between two lines, rather than line and N .. but you should still get an earth loop, although it would appear to be 115V rather than 230V to earth (which might fool some testers). Maybe some voltage readings L/N, L/PE, PE/N without the link might enlighten.

   - Andy.

Some of Pramac are telling me that it does not require an earth? The other half of pramac have said i need to put the link between N-E with an earth rod connected to the plug that goes into the Gen?

In a way both are true.  A generator can either be setup as a local TN-S system (with an electrode and a N-PE link) (as per section 411 of BS 7671) or as a floating or separated system (section 413 or 418.3). The latter remains safe on 1st fault and so doesn't require automatic disconnection or earthing, but has some disadvantages especially when feeding an extensive installation, so typically is reserved for small generators (≤3kVA) and/or portable setups.

   - Andy.

Looking at the brochure file:///home/mpj/Downloads/Brochure%20S-SP%20Series_ENG_LR.pdf

There is nothing untoward about this machine, and it does not seem to have a complex controller or autostart - such things can be confused under low load conditions.

Indeed, as built the genset itself will be IT - so the windings 'float' - neither end nor middle should be earthed until you add a link of your own - a quick flick with the meter on ohms will verify the winding isolation or presence of a link.

As others have alluded..

All gensets used to supply a house must be wired TNS so there is connection from one end of the genset winding that we shall call neutral and a local electrode, and the circuit CPC, so that ADS operates on L-CPC  fault. But there should be one earth neutral bond and one only, so when the house is on genset, then the NE link from the mains supply  is 'put of loop' or the RCDs see it as a fault. This is normally achieved by having a change-over that switches both live and  neutral.

Double check there is not already an NE  link in the changeover box and that polarity is preserved correctly. If it helps. take some pics and post them here and we can probably be more specific.

Mike.