Ask the generator vendor about 2-wire start. Some transfer switches
require 2-wire start, so the generator probably has a way to do it. If
you can do 2-wire start, then the rest is straight forward.
Generac Guardian can do it with a slight re-wire and a secret code
entered on the control panel. On the Guardian, the starter battery
charger runs on A/C which normally comes from the transfer switch, so I
had to do a little hack to make that charger work. I did this at a site
to get it running before the utility power was set up.
Once you have 2-wire start configured, you connect the 2-wires to a
relay. I used an NC relay and opened it to turn the genny off. The
idea being that if batteries ever ran down to zero, the relay would
close and start the generator. Since it was temporary, I just had a
cron job on a server start the generator at a certain time and then stop
it 8 hours later. It could just as easily have monitored battery
voltage and started the engine at 11.5 Volts (or whatever).
If it was permanently off-grid I'd find a way to monitor the state of
the starter battery, and connect the starter charger to an inverter
running off the solar batteries.
------ Original Message ------
From: "Jesse DuPont" <[email protected]>
To: [email protected]
Sent: 2/3/2017 11:05:37 AM
Subject: Re: [AFMUG] I Want
Does anyone have a document or wiki that describes how to take an
off-the-shelf AC standby generator and use it at a solar/DC site? I'm
assuming starting would be via remotely-operated or
conditional-logic-operated relay based on battery voltage? Anyone done
it and care to share the nitty gritty?
Jesse DuPont
Network Architect
email: [email protected]
Celerity Networks LLC
Celerity Broadband LLC
Like us! facebook.com/celeritynetworksllc
Like us! facebook.com/celeritybroadband
On 2/3/17 9:02 AM, [email protected] wrote:
And on a standby generator, if it is a true DC generator the brushes
will last forever. But it is probably an alternator/rectifier.
AC generator with redundant rectifiers is bound to be the best value.
From:Adam Moffett
Sent: Friday, February 3, 2017 8:56 AM
To:[email protected]
Subject: Re: [AFMUG] I Want
However you get there, the nice thing about DC is you don't have to
stay at 3600 RPM. It's a big part of why inverter generators last so
long on small loads.
------ Original Message ------
From: "Mark Radabaugh" <[email protected]>
To: [email protected]
Sent: 2/3/2017 10:29:29 AM
Subject: Re: [AFMUG] I Want
From an engineering standpoint I would expect a DC generator to be
higher maintenance than an AC generator. True DC generators have
brushes that wear while AC generators have very little other than
bearings to wear out. Alternators (like your car has) are actually
AC generators with a rectifier pack to turn the AC back into DC.
When your alternator bites the dust about half the time it’s the
rectifier that fails, the other half of the time it’s the bearings,
with a small percentage of winding or other failures (yeah - I know
that’s more than 100%).
Our high reliability sites have standby AC generators with 500 gal
propane tanks, a rectifier shelf, and ~24 hours of batteries. So far
they have been very reliable.
Mark
On Feb 2, 2017, at 5:45 PM, Chuck McCown <[email protected]> wrote:
Well, it certainly would protect you in the event of rectifier
failure.
From:That One Guy /sarcasm
Sent: Thursday, February 02, 2017 3:44 PM
To:[email protected]
Subject: Re: [AFMUG] I Want
if youre doing a standby generator at a dc site, even an AC fed DC
site, wouldnt it be more efficient to use a dc generator, with less
maintenance?
On Thu, Feb 2, 2017 at 4:29 PM, Adam Moffett <[email protected]>
wrote:
Ah yes, I see.
------ Original Message ------
From: "Chuck McCown" <[email protected]>
To: [email protected]
Sent: 2/2/2017 5:28:39 PM
Subject: Re: [AFMUG] I Want
Perfect for off-grid solar backup.
From:Adam Moffett
Sent: Thursday, February 02, 2017 3:27 PM
To:[email protected]
Subject: Re: [AFMUG] I Want
Man, sounds like a lot of money for 6kW.
Variable speed must save a lot of gas though.
------ Original Message ------
From: "Chuck McCown" <[email protected]>
To: [email protected]
Sent: 2/2/2017 5:25:35 PM
Subject: [AFMUG] I Want
Have to come up with a reason but I want it:
https://www.norwall.com/products/Kohler-6kW-Variable-Speed-Direct-Current-Generator-with-Oil-Make-Up-Kit-48-Volt-DC-6VSG?cid=google_feed&dfw_tracker=6374-6VSG-QS13&gclid=COWuo4-68tECFUdlfgodl8oG_A
<https://www.norwall.com/products/Kohler-6kW-Variable-Speed-Direct-Current-Generator-with-Oil-Make-Up-Kit-48-Volt-DC-6VSG?cid=google_feed&dfw_tracker=6374-6VSG-QS13&gclid=COWuo4-68tECFUdlfgodl8oG_A>
--
If you only see yourself as part of the team but you don't see your
team as part of yourself you have already failed as part of the
team.
