The Accidental Smallholder Forum

Smallholding => Equipment => Topic started by: Penninehillbilly on August 10, 2017, 02:04:16 pm

Title: Electric fence - transformer
Post by: Penninehillbilly on August 10, 2017, 02:04:16 pm
Hi
I have 2 Rutland battery operated energisers, and a Gemini which is mains or battery.
Rather than heaving heavy batteries about, what are thoughts on running a Rutland energiser off a 12v transformer?
Obviously Transformer would be inside, dry, i currently run Gemini from barn or house, different fields, but could do with having both fields in use.
Any opinions please?
Title: Re: Electric fence - transformer
Post by: mab on August 10, 2017, 02:23:03 pm
It should be fine; though I would tend to choose a regulated transformer  (the modern lightweight plug-in transformers are regulated), at least 0.5A (the energiser probably averages less than 0.2A but may pull more for a moment when it zaps).
Title: Re: Electric fence - transformer
Post by: Penninehillbilly on August 10, 2017, 04:11:32 pm
Thanks, i was wondering about amps. 
Title: Re: Electric fence - transformer
Post by: Still playing with tractors on August 11, 2017, 12:53:21 pm
You would need a transformer with rectification to change from AC to DC with a current loading of at least the same as the battery, to allow for transient loads of the fence energiser clicking on and off. you may find the set up to be some what heavy as the transformer and rectifier will have to be either a ferrite core or a toroid type and not a switchmode type.

let me know if you need any further info. 
Title: Re: Electric fence - transformer
Post by: Penninehillbilly on August 12, 2017, 01:21:25 am
Thanks, husband said that today, I thought transformers converted to DC as part of process.
Starting to sound complicated.
The Gemini has a standard plug/transformer, so i thought something like that would do. 
Title: Re: Electric fence - transformer
Post by: Penninehillbilly on August 12, 2017, 07:29:15 pm

Back again


cant put the picture on, but looks like a phone charger, maybe a bit bigger


This is the sort of thing I was thinking of?
12v
converts to DC.
would obviously adapt it to join on to normal energiser leads




Model:F24W1
Entree (Input):100-240v~50/60Hz 0.6A
[size=78%]Sortie (Output): +12v ---2A[/size]
Convert AC 100v-240v to DC 12v
DC 12 V, 2A: Perfect to supply power for aquarium led strip lights, or led strip light for home use.
3 pin UK plug
It is Centre Positive and has a 2.1mm x 5.5mm jack
Adapter wire length: 150cm


not sure of ampage?
fence unit says 12v 25ma?

Title: Re: Electric fence - transformer
Post by: mab on August 12, 2017, 09:08:14 pm
I must admit i'd assumed you knew to select d.c. - oops!


I'd be happy with that transformer you've selected - it is a switchmode which SPWT doesn't like, but I'm a bit more comfortable with them as long as it's not a really dirt-cheap from China job. It's rated 2A vs your energisers average required 0.025A [size=78%]so it shouldn't have a problem supplying the peak currents when the energiser zaps, and being a switchmode, the output should be regulated to 12v.[/size]
[/size]
[/size][size=78%]The type of transformers spwt is referring to are more robust (and nowadays more expensive) but sometimes come in unregulated outputs which can rise to 19 - 20v when they're set to 12v which is why I'd advise only using one that says it's regulated. [/size]
[/size]
Title: Re: Electric fence - transformer
Post by: Penninehillbilly on August 12, 2017, 11:54:33 pm
Thanks mab, yes, I knew I'd be looking for a dc output, but wondering whether one of these would either blow up, blow the house fuse or damage the energiser, have a vague knowledge, but rely on OH to keep me straight. He doesn't always want to know unless it's his idea LOL.
Was going to ask what you meant by spwt,  then it twigged and all made sense.  :)
I shall approach he who is occasionally obeyed.
Thank you.