Back-up Power: What One Ham Did To Reduce Inrush Current On His AC Compressor

2 views
Skip to first unread message

David Tanks

unread,
Jan 29, 2026, 6:04:59 AM (6 days ago) Jan 29
to valleyhams
Very interesting!

David AD4TJ

----- Forwarded Message -----
From: Alan - W5ARM via groups.io <w5arm.mail=gmai...@groups.io>
Sent: Wednesday, January 28, 2026 at 08:26:17 PM EST
Subject: Re: [Ham-Antennas] WAS: How best to install utility pole halyards?? NOW Back-up Power

I did a 22kW Generac install at my home QTH in Texas.  The house-build was completed in July of 2020.  During construction, I specified a "transfer-switch ready" loadcenter to be installed (made by Siemens), as I had planned — early-on — to install a GenSet. We're in a pretty rural area, and power outages are not uncommon.
 
We moved in, in July of '20, and the generator itself was ordered in August (right in the middle of "covid").  Unfortunately, Generac was more-or-less shut down because of the pandemic BS, and therefore my GenSet didn't ship until late March — 7 months after ordering.
 
Anyway, once it arrived, I did the entire install myself, including the concrete pad, gas lines & tank, and all electrical (I'm a retired electrician and industrial mechanic).  The propane tank was brand-new and purchased outright (I own it), so no 'leases' to deal with, and I can buy fuel from any supplier. 
 
The GenSet will supply the whole house with power (including the A/C and heatpump, and water heater) and has run many times during outages, since going online in 2021. Most outages have been short-duration - 30 min's to an hour... But one outage was 11 hours!
 
The only 'external device' I needed to install, was a 'soft-start' on my A/C compressor, to reduce the inrush current on start-up. It made a huge difference, dropping the instantaneous start-current from >85 amps, to around 40 (measured with a Fluke 'amp-clamp').  Virtually no "lugging" now on the Generac, during A/C starting.  As a bonus (many don't realize this), the soft start also reduces starting 'wear' and stress on the compressor, adding greatly to the life of the A/C condenser unit - even without a generator. HERE: Hyper Engineering Starting Test
 
The soft start unit is HERE: Eltwin Hyper Sure-Start. They can be purchased on Amazon, and through other suppliers.
 
While diesel generators are less expensive to run than propane units (less gallons-per-hour of fuel consumption), as Chuck mentioned: Diesel does have some long-term storage issues, as well as the well-known "gelling" issues at low temperatures (even if it is 'treated'). And gasoline would be even worse, as far as long-term storage!  Propane - basically -  keeps forever.
 
Here's a pic of my install...
 
--
73,
~Alan
_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

View/Reply Online (#21708) | Reply to Group | Reply to Sender | Mute This Topic | New Topic


Gordon Batey

unread,
Jan 29, 2026, 9:22:28 AM (6 days ago) Jan 29
to David Tanks, valleyhams

Greetings to all,

 

My two cents worth…

 

I installed a 20KW Cummings Diesel generator and automatic transfer switch at my home in 2011. 

I purchased the equipment from WG4T (sk) who sold and serviced generators for many years.  I had a concrete pad installed.  A local ham, Mathew KD4UPL installed the transfer switch and did all of the wiring.  At the recommendation of WG4T I use number 2 home heating oil as the fuel.  When the supplier for my oil fired furnace automatically fills my furnace tank, he tops off the generator tank with 3 or 4 gallons (it has about 85 gallons capacity).  About 3 weeks after the installation was completed, we experienced a derecho storm here in Virginia.  The generator automatically started about 8:30 pm Friday night and ran until power was restored late Monday afternoon.  A total of 67 hours.  I don’t experience many power outages but it has operated almost without failure for over 15 years.  I turned off the commercial power for home station field day operation during the covid event.  The generator preforms a automatic self-test with a no load run once a week for about 15 minutes. 

 

73 Gordon WA4FJC

Gordon Batey

unread,
Jan 29, 2026, 10:06:36 AM (6 days ago) Jan 29
to Gordon Batey, David Tanks, valleyhams

PS…

 

This genset is equipped with a coolant heater (100 degrees) and a Battery Tender.  Works real well.

 

Gordon

--
--
You received this message because you are subscribed to the Google
Groups "ValleyHams" group.
To post to this group, send email to valle...@googlegroups.com
To unsubscribe from this group, send email to
valleyhams+...@googlegroups.com
For more options, visit this group at
http://groupsgoogle.com/group/valleyhams?hl=en
Please do not send jokes and junk e-mail on this list - Let's use it for our various hobbies, public service, communications and any good useful information for our hobbies and Events.
---
You received this message because you are subscribed to the Google Groups "Valley Hams" group.
To unsubscribe from this group and stop receiving emails from it, send an email to valleyhams+...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/valleyhams/000001dc912a%24ab5f3670%24021da350%24%40compuserve.com.

Cameron Mac Millan

unread,
Jan 29, 2026, 1:41:18 PM (6 days ago) Jan 29
to valle...@googlegroups.com
Out of curiosity (and I realise this was installed 14 or so years ago),
do you happen to know which automatic transfer switch was used?

We're looking at installing a military tactical quiet generator at some
point, probably in the 10 to 15 KW range, and the house tie is something
I've no practical experience with. Been doing a lot of research, but am
always happy to hear from people who have been there before me.

This may or may not be coupled to a whole-house UPS at some point, but
that's very much a down-the-line consideration.

73,

- Cameron (KR4CKA).
Reply all
Reply to author
Forward
0 new messages