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Re: Another Coolant Alarm Issue
Posted: Wed Apr 20, 2016 8:00 am
by haydn callow
Ours has a short delay built in so sloshing about is not a problem.....also it self tests every time you switch on the ignition. We do not use a 555
Re: Another Coolant Alarm Issue
Posted: Thu Apr 21, 2016 12:17 pm
by John_H
haydn callow wrote:Ours has a short delay built in so sloshing about is not a problem.....also it self tests every time you switch on the ignition. We do not use a 555
Aha .. those are both very good ideas

- I'll see if I can do that as well with my circuit.
So, my design was from the 70's - now just realised how ancient the germanium transistor is!!

still, I might have a few in my attic.
Re: Another Coolant Alarm Issue
Posted: Thu Apr 21, 2016 1:07 pm
by haydn callow
We also encapsulate the gubbins in epoxy......makes it bombproof. We have virtually no failures..less than 0.25%, but it did take us 3 years and the help of this forum to achieve this reliability......no Chinese components was the break through.
Re: Another Coolant Alarm Issue
Posted: Thu Apr 21, 2016 3:05 pm
by teenmal
John_H wrote:Thanks to all for the advice on getting a low coolant alarm.

I used to have one on my Land Rover some years ago which I remember was a fairly simple device to make and install into the header tank. I wonder if I've still got the design for it?. I see a commercial one mentioned a lot on here but
it does seem to be a considerable amount of cash ...
You can purchase very reasonably priced alarms on eBay or direct from the seller , the guy that makes them has a very good reputation on a few Forums. If you are bothered by Sloshing just fit a longer screw.
http://www.ebay.co.uk/itm/121532137275? ... EBIDX%3AIT
Re: Another Coolant Alarm Issue
Posted: Thu Apr 21, 2016 7:08 pm
by Simon Jones
If you go for that one, don't forget to press the test button everytime you turn the ignition on....

Re: Another Coolant Alarm Issue
Posted: Thu Apr 21, 2016 7:14 pm
by John_H
teenmal wrote:You can purchase very reasonably priced alarms on eBay or direct from the seller , the guy that makes them has a very good reputation on a few Forums. If you are bothered by Sloshing just fit a longer screw.
http://www.ebay.co.uk/itm/121532137275? ... EBIDX%3AIT
Thanks, I did see those kits but wasn't so impressed with them. I think I'll have a go at DIY and if that fails, get a Haydn kit !
Re: Another Coolant Alarm Issue
Posted: Thu Apr 21, 2016 10:28 pm
by g8dhe
If you read the FB forums, there are reports of failures on the Ebay versions, none so far have been very forthcoming as to what / how /why.
Likewise 3 reports now of Solar panels being ripped of of roofs by the wind or screws becoming loose, again these are all reports from cheaper Ebay versions where very little consideration has been given to mounting the panels and the forces that will occur.
Its interesting to note that the two rather more expensive, well tested designs that have originated from people in this forum do not seem to have these problems .....