vermilye wrote:
3 light testers, surge protectors & other EMS devices cannot actually detect an open ground because they have no way of detecting an open connection between the ground wire & the earth - they cannot reference the earth. Instead, they "look" for the bond connection that usually takes place at the service entrance. If that connection doe not exist, the device assumes that the ground is open.
While a good ground is critical when the power source is the local utility, it is not necessary (or, according to many, even desirable) with a locally supplied source. Floating the system without a neutral bond is allowable by both the NEC & OSHA for 120V low power (under 5KW or so) systems.
Here is an interesting PDF that discusses bonding & grounding of small generators that is worth reading. It explains the reason the utilities ground their systems, and why small portable systems don't always require grounding or bonding.
:h If I'm correctly interpreting the following excerpted from this .pdf you linked to my EU2000i genset is in fact a "locally supplied source" so when I plug my trailer into it I
should bond the neutral to the ground ... or am I misunderstanding this?
"A neutral conductor shall be bonded to the generator frame if the generator is a component of a separately derived system.
Consider this question. Is a generator on a construction site supplying only cord-and-plug-connected equipment (saws, drills, lights, etc) through the receptacles mounted on the generator considered a separately derived system? The answer is a resounding "Yes!". It is always a separately derived system under those conditions and consequently the neutral must be bonded (electrically connected) to the frame of the generator."Given the above it would seem to me my trailer is a "cord-and-plug-connected equipment" and therefore I
should bond the source neutral and ground whether that portable source is my 1000 watt inverter or 2000 watt EU2000i inverter generator. Is this not contrary to what
Gdetrailer and others are saying? :@ :h