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Generators / Re: ST3 Noise and vibration
« on: Today at 01:30:15 AM »
Glad that it was just the usual ST-3 split phase snafu. They can really moan and groan with sounds that say imminent failure.
You can carry a split phase situation with the ST-3 by adding a transformer with dual 115V windings, or adding two transformers with 115V secondaries if you need more than 1500W of power. The load on each 115 split phase must be below the rating for that secondary winding. Spendy and a bit wasteful (40 watts iclle current for 2- 1500W tranformers) but its the best you can do with an ST-3, typically.
You can drive the Antec primaries with either 115 (primaries in parallel) or 230V (primaries in series).
Regarding grounding of the neutral. Sure, its nice to have the neutral grounded in one and only one location- if you ever intend to power the greenhouse from the house service - or someone might do that via extension cord, then making the greenhouse a normal code compliant sub panel with separate neutral and grounds being supplied by a grounded neutral/safety ground generator is probably best- assuming generator unplugged if house power is connected. If the greenhouse was remote and so the generator is the only potential power source, then it could be set up just like main panel with the grounding rod connecting to the ungrounded generator ground and neutral tied to that at the panel.
Multipoint grounding of the neutral is a no-no as it causes current to flow through the safety ground which can then act as an "alternate neutral". Bad news as the safety ground is NOT intended to be a current carrying wire within the home, it should be a relatively safe earth ground except only for clearing faults in an emergency.
You can carry a split phase situation with the ST-3 by adding a transformer with dual 115V windings, or adding two transformers with 115V secondaries if you need more than 1500W of power. The load on each 115 split phase must be below the rating for that secondary winding. Spendy and a bit wasteful (40 watts iclle current for 2- 1500W tranformers) but its the best you can do with an ST-3, typically.
You can drive the Antec primaries with either 115 (primaries in parallel) or 230V (primaries in series).
Regarding grounding of the neutral. Sure, its nice to have the neutral grounded in one and only one location- if you ever intend to power the greenhouse from the house service - or someone might do that via extension cord, then making the greenhouse a normal code compliant sub panel with separate neutral and grounds being supplied by a grounded neutral/safety ground generator is probably best- assuming generator unplugged if house power is connected. If the greenhouse was remote and so the generator is the only potential power source, then it could be set up just like main panel with the grounding rod connecting to the ungrounded generator ground and neutral tied to that at the panel.
Multipoint grounding of the neutral is a no-no as it causes current to flow through the safety ground which can then act as an "alternate neutral". Bad news as the safety ground is NOT intended to be a current carrying wire within the home, it should be a relatively safe earth ground except only for clearing faults in an emergency.