Generator Exercise

Proper transfer switches are expensive to buy and install... but an economical, safe, and LEGAL way of doing rapid transfer, is to install a BREAKER INTERLOCK KIT, and a dedicated backfeed breaker.  Here's how it works:

You install a circuit breaker who's purpose is to provide feed INTO your breaker panel from your generator.  Wiring to this breaker can be as simple as a range cord to your generator.

A sliding plate, installed on the breaker panel, blocks your generator breaker anytime the MAIN breaker is ON.  When the GENERATOR is engaged, that same plate prevents the MAN from being thrown.  The plate, therefore, provides exclusive interlock.  One of the issues with this concept,  however, is that it doesn't limit what load your generator could wind up pulling... you could easily overload a small generator, so one must turn off breakers to all devices that are unnecessary.

This is a very economical way to go.  My service is square D.  Square D markets a lock out expressly for this.

  Hey Dave Kamp,,,,Very informative and interesting reading,,,how come you didn't go get hired as a college professor and make loads of them dollars they handing out,,,,

   Sterno under a propane tank tho,,?????

 I only remember one time going thru a really cold spell down here to consider wrapping our small 200 gallon tank with electric heat tape,,,what are your thoughts on that,,,??? 

desertjoe wrote: how come you didn't go get hired as a college professor and make loads of them dollars they handing out,

Well... I've taught college classes... but I taught a whole lot more at railroads and technical facilities.  My experience has been that most colleges are not interested in professors who teach practical science, applied physics, or concordant technological history.  I'm not the kind of guy who will stand in front of a class for purpose of sociopolitical indoctrination.  I'm a pragmatic polymath, not a tool.

Simple.

The generator is a 750KVA machine.  It has essentially a locomotive engine... 1300hp or so... driving a big generator.  It's 38ft long, 11ft wide, and 12ft tall, sitting on a concrete base a foot off the ground.  There's a huge transfer switch, and two power transformers sitting on the base about 30' to one side, and under the machine is a fuel-oil tank that's every bit of 3000 gallons.

What they did here, was not only foolish, it was a blatant insult to the taxpayer.

Limit the lighting.  Adding up all the high-bay and outdoor illumination, My house and farmstead has somewhere in the vicinity of 6500w of lighting.  It USED to be much higher, but I've converted ALL the house to LED, and one big driveway floodlight... now it's 3800w or so... but MOST of that, is the merc-vapor bay lights in the barns and driveways.  The total house lighting... everything on... is 1000w... but when I'm on emergency power, I only use small lights in strategic places around the house.  My total emergency lighting load in emergency state, is only 140w.  With that, I can walk to any place in the house or garage, with sufficient illumination to carry out maintenance tasks, and wait out a storm... and more often than not, I have all but a few of those lights on.  That means I can run those lights on a car battery and a cheap inverter.

Sequester unnecessary loads.  Don't run laundry, dishwasher, air compressor, hair dryer, electric heaters, vacuum cleaners, arc welders, rock crushers, centrifuges, or other things that are really hungry.  This can be done by just exercising restraint and turning things off... but another way, is to step up to your breaker panel with red, yellow and green stickers, and mark each breaker with a color... green being always on... yellow meaning 'only if absolutely necessary', and red being NEVER... when on emergency power.  Still another way, is to have emergency loads on a dedicated panel that your generator feeds... everything else is powered only when utility is available.

Plan ahead... simple choices can have a profound impact on how an outage affects your life. 

For example:  A single refrigerator-freezer, will outlast a separate fridge and chest-freezer when power is out.  The frozen foods serve as an excellent chiller for refrigerated foods, whereas the separated unit refrigerator will rise in temperature faster, and cause earlier spoil.  The alternative, is having an extremely large refrigerator, is to have your refrigerator stocked-to-the-ledges with non-perishable chilled (think beer, soda, bottled water).  After the power has been off for three days, all that cold liquid will help keep the dairy, meat, and vegatables cool.  

Another example:  You have a 1/2hp sump pump that, under bad conditions, cycles on once every two minutes for 10 seconds.  It pulls a start surge of 25A for a half second, and pulls a constant 9 for the remaining  9.5 seconds.  Under the same circumstances, a 1/5hp sump pump cycles on once every 2 minutes, and runs for 20 seconds, pulling 7A, and running at 3.  Effectively, the smaller pump runs longer, but draws less overall power, and subjects the generator to a much lower start surge event.  As a 'belt-and-suspenders' alternative, mount the bigger pump in the sump so that it's switching point is 'above' the smaller (i.e. triggered by a really high secondary switch) so that if the small one fails, the big one will jump into action.

Another example:  Find all your heaviest-starting loads... pumps, fans... things with motors... install time-delay relays on them all... and set them to DIFFERENT delay times.  By doing this, when you intially apply power to the house after an outage, you don't have a situation where every load comes on at the same time... instead, they come on at intervals, so the start surge applied to your generator is substantially lower.  It's also a good idea to put about a 5 minute delay relay on anything refrigeration and air-conditioning... EVEN if that  unit is NOT on generator... refrigeration compressors do NOT bode well to having power shut off, and reapplied in a short timeframe-  the compressor is taking gaseous refrigerant, and mashing it down, cooling it off, for purpose of changing it into a liquid.   Once the compressor is stopped, that refrigerant has 'head pressure' against the pump, and refrigerant condensation at the pump can cause the compressor to be stalled against it's load... restarting it puts a serious hurt on the compressor... instead, once it's shut down, it must STAY shut down for a while (at least a couple minutes) before restarting.

Dusty MI wrote: ""...install a BREAKER INTERLOCK KIT, and a dedicated backfeed breaker.''"  If you size the breaker that the generator feeds the panel, to the size of the generator, then that breaker protects the generator from overload.

This is true, and it's a very good idea to do so, however, it will be at risk of nuisance trips when the generator picks up a heavy surge load... an HACR breaker type is a wise choice for interlock use as a result.