Hydrochloric acid?

[Jonzjob]

I am trying to find out where I can get a small amount of hydrochloric acid? I need it to clean the probe on my Chemigem automatic chlor/PH  controller. About 1/2 pint would be enough, but I can't remember seeing it anywhere. I doubt that it's worth looking in a pool shop as when I have asked for sulphuric acid before I have been met with blank stares and asked what it's for. Tell them it's to drop the PH and get the answer that it isn't H2SO4 I need but PHminus! Look on the bidon and it's sulphuric acid [:-))]

I am also trying to find out what size capacitor I need to connect across the output of my pool pump motor contactor to stop the arching when it's operated? It is causing a spike on the power that the pool controller doesn't like.

Any ideas about either please?

[Théière]

Hi John,  Almost any Brico stocks hydrochloric acid in 1 litre, 5 litre and some 20 litre, also good for pH- really the pool shop staff know very very little about what they are doing, it's why I intervene when someone says "Go to your local pool shop"

Hmm, interesting with your pump not sure on that one.

[Jonzjob]

Ta TP.

The controller also has an electronic timer for the pool pump, which I use because it's so much easier than the elec/mech rubbish available and it keeps time even if there is a power cut. No need to reset anything. That switches a contactor for the pump and after a phone call to Pool Controles in Aussy this morning the techie made the suggestion of the cap across the contactor. I know of an electric motor place in Carcassonne and they will probably know and have one in stock? All I will have to do is work out what to say, 'cause they don't speak English [:-))]

Such fun [8-)]

[Théière]

Yes no problem with the idea just wouldn't know where to start capacitor value wise. I don't use the mechanical timers for the reason you state and they breakdown too frequently (they are cheap) I use the electronic ones as they have a battery backup so no re setting even after 8-9 months over winter close down. If only I were nearer, Carcassonne is such a way down.

[Jonzjob]

My winter prep is pretty straight forward. I unplug the controller and cover the solar tubes. I had a cover made for them. The material is the same as the tauntliner trucks use on thesides of the trailers so should last OK. I had them made just outside Stroud in a place I know quite well. The floating security cover is put on and sometimes I put a light weight winter cover on to stop a load of rubbish getting in too, but not always?

The solar controller has the frost setting enabled and if the temp dropps too far it starts the solar and the pool pump for 5 minutes every so often. so far we had 2 weeks of sub zero temps last year and no problems, so the system certainly works. The hot side of the solar has just water, no anti-freeze. As you know TP, with tubes the only fluid in the hot side is in a manifold and not in the tubes, so there isn't very much fluid to protect and what there is is well insulated.

[Gluestick]

Jonz:

I am presuming your electronic timer enables (turns on) a simple electro-mechanical relay switch and it is that is causing the contact arcing?

Therefore what you need is what is called "A Snubber": which is a simple capacitor-resistor network.

See here:

http://www.electronics-tutorials.ws/io/io_5.html

Values? No idea without: pump motor size? Motor type? (i.e. single phase induction? Resistive Start-Induction Run? etc).

Basically the Capacitor must resist both the working voltage and the spikes from back-emf thru the switch relay coil.

For cleaning any corroded metal, I always keep a litre of phosphoric acid.

[Jonzjob]

That's correct GS. It switches a contactor to a 1100w single ø cap start induction motor. I'll pop into an elect motor place in Carcassonne as soon as I get the chance. They seem pretty well switched on (no pun intended???) in there and will probably have one for the job. All I need to do is to sort out some language to use?

The hydrocloric acid is to dip me probe in [:-))] and I found some in a local brico so no problems there. Could make me eyes water if I drip it in the wrong place [:$][blink]

[Gluestick]

[quote user="Jonzjob"]That's correct GS. It switches a contactor to a 1100w single ø cap start induction motor. I'll pop into an elect motor place in Carcassonne as soon as I get the chance. They seem pretty well switched on (no pun intended???) in there and will probably have one for the job. All I need to do is to sort out some language to use?

The hydrocloric acid is to dip me probe in [:-))] and I found some in a local brico so no problems there. Could make me eyes water if I drip it in the wrong place [:$][blink]

[/quote]

This should serve, Jonz.

http://www.conrad.com/ce/en/product/503139/RC-snubber----Finder----9902023009

Connect the modular Snubber across the contacts which switch the mains load.

If you contact Conrad, France, they will post quickly. I've used them before on a number of occasions when in France.

[Théière]

Hi Gluestick and John,  Isn't that a capacitor run motor rather than a capacitor start? never heard a centrifugal  switch cut out on a domestic pump?

Handy link Gluestick.

[Gluestick]

[quote user="Théière"]Hi Gluestick and John,  Isn't that a capacitor run motor rather than a capacitor start? never heard a centrifugal  switch cut out on a domestic pump?

Handy link Gluestick.

[/quote]

Electric motors these days, Thé come in a dazzling variety of flavours! Jonz states the motor is rated at 1,100 watts; well at 230V AC, that's 3/4 horsepower in old money. Quite a chunky lump, then.

http://en.wikipedia.org/wiki/Induction_motor

I have a venerable old single phase 1/4 motor which for years I've used as a rough slow-speed grinder, polisher: centrifugal start - capacitor run

Increasingly today, smaller induction motors use either a separate starter winding and a PTC (Positive Temperature Co-efficient Thermistor) rather than the old centrifugal starter; (typically, fridge-freezer motors) or are capacitor start-capacitor run.

[Gluestick]

Jonz: having thought a bit more about this, I do wonder if the problems with the timer are mains transients and "spikes", rather than contactor points arcing?

When the pool pump motor starts, the current inrush on a motor rated at 1,100 watts would be pretty enormous and on French wonderful campagne mains supply, would usually cause a voltage droop.

Most solid state as against mechanical timers use a relay to switch the load: therefore, the timer circuit itself is isolated from the effects of the load switching.

Therefore, a simple mains filter for the supply feeding the timer circuit should solve your problem.

Conrad should have these: the last one I bought came from Maplin in UK: simple plug in thing to remove interference from the kitchen micro-hi-fi every time fridge-freezer turned on etc.

[Jonzjob]

When I did my electrifical training there were 745.699872, approx, to 1 hp so that makes the pump motor even more chucky at about 1.4751242977 [:-))][:D]

And yes, it is one of those kind of motor and I ain't taking it to bits ti find out which [Www][Www]

Edit :  - Our posts crossed there. When we changed our Livebox we got another surge protector with it and that got plugged into the feed for the Chemigem pool controller and that made no difference. So as it stands it should protect the controller from any surges caused by the motor starting, but I doubt it would stop any arching caused by the contactor switching the pump on/off?

I will see if I can get a snubber ordered, but on the Conrad.fr site they want 3.70€ for the bit and 8€ for the postage [:-))][:-))] The dammed thing is only the size of a box of Swan Vestas!!! There isn't a rush as it's been going on like this for a couple of years now, so I'll get into the motor place next time we go into Carcassonne.

I agree with TP, that's a good site you posted for the elect theory..

[Théière]

[quote user="Jonzjob"]When I did my electrifical training there were 745.699872, approx, to 1 hp so that makes the pump motor even more chucky at about 1.4751242977 [:-))][:D]

[/quote]

My old 3/4hp under normal running load used to burn 723 W/h

If only you weren't so far down the road John,  could get that electricity bill way down to 100-120w and then no nasty spikes.

[kiruzsal]

Oh my God, no

[Jonzjob]

OK??? Which god is yours and why 'no' [8-)]

[halfblind]

Just signed up and first post ! A troll I would assume. Or maybe someone from FE ?

[Jonzjob]

1/2blind, I am not sure if it's you that's 1/2blind or me 'cause I only just saw your reply? What are you on about pretty please???

All wrapped up for the winter now. The snubber is now fitted for the

pump contactor and after 3 daze the display on my Chemigem pool

controller is still showing what it should and seems to have given up

flashing at me?? [:-))] So a very BIG ta to you GS..

I don't drain owt down for winter. Just cover the solar tubes, put the floating safety cover on with a winter cover over that. If it gets down below 5ºC the solar control puts the pump on for 5 mins each hour and below 2ºC then 20 mins/hour. That keeps the water flowing and even although we had very sub temps for 2 weeks in 2013 there were no problems.

Thank you again GS. I'll keep an eye on the display and see if it fails again? I'll let you know how it goes.

Edit  :  -  That ta should have been huge [8-)]

[halfblind]

[quote user="Jonzjob"]1/2blind, I am not sure if it's you that's 1/2blind or me 'cause I only just saw your reply? What are you on about pretty please???

[/quote]

I was referring to the post from kiruzsal which you commented on - refferrals to "god" ?

Never mind, go and have a lie down ;-)

[Gluestick]

[quote user="Jonzjob"]1/2blind, I am not sure if it's you that's 1/2blind or me 'cause I only just saw your reply? What are you on about pretty please???

All wrapped up for the winter now. The snubber is now fitted for the

pump contactor and after 3 daze the display on my Chemigem pool

controller is still showing what it should and seems to have given up

flashing at me?? [:-))] So a very BIG ta to you GS..

I don't drain owt down for winter. Just cover the solar tubes, put the floating safety cover on with a winter cover over that. If it gets down below 5ºC the solar control puts the pump on for 5 mins each hour and below 2ºC then 20 mins/hour. That keeps the water flowing and even although we had very sub temps for 2 weeks in 2013 there were no problems.

Thank you again GS. I'll keep an eye on the display and see if it fails again? I'll let you know how it goes.

Edit  :  -  That ta should have been huge [8-)]

[/quote]

My pleasure, Jonz.

Been otherwise occupied for too long, working -again! - 24/7. Haven't accessed the forum, apart from one other post.

Roll on Spring!

GS