Power source for Varrox - have I bought a pig-in-a-poke?

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The 150 watts used by the Varrox is almost equivalent to leaving the lights on on your car. If your car is a petrol one with say an engine less than 1600 cc it should be OK for 1/2 hr, If the car is diesel and bigger than 1600cc you should get well over 1/2hr. May be sensible to do a few hives and then run the engine for 10mins or so.

So are you able to tell me how many times I can fire the 1500 Watt Varrox for 2.5 minutes without depleting my standard saloon-car battery?

Rab's on the ball there - but let's make it 3 mins to make the sums easier: 1 hour divided by a 3 minute 'dose', will give you 20 'doses' which will have removed a total of 12 Ah.

Will your car battery withstand a loss of 12 Ampere/hours and still start the engine ? - if it's in good condition and reasonably well charged beforehand, I'd have thought so.

So work on 20 'doses' maximum, before running your engine to re-charge the battery.

But - even though I'm probably being over-conservative here, I'd recommend sticking to 10 doses during the first time out - just to be on the safe side. Nothing would be worse than sitting on the side of the road during winter with a battery unable to start the engine 'just 'cause this idjut on a beekeeping site told me it would be ok'. :)


which is pretty-much what MikeT has just said. Must try to be quicker on the keyboard in future ...
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Thanks folks for making it clear. I seem to remember learning A=W/V for O level physics but that was in the 1950s........ Yes, 150 not 1500 watts.
I did a test run on one hive today. Made the bees roar but no mice jumped out.
...I did a test run on one hive today. Made the bees roar but no mice jumped out.
A few things I found helped.
  • If you can, free the entrance blocks a day or two before. A lot of propolis on the block and it can be a fiddle to get it out, then the bees start reacting and you have quite a few around the entrance when you're trying to wedge foam in.
  • Easier to weigh out the oxalic crystals beforehand into small folds of kitchen foil. One folded package for one 2g dose, make up a couple of spares. A small scoop provided with the varrox got anywhere from 1.2 to 2 g, the long crystals of oxalic are hard to estimate by volume.
  • If the varroa board is already in the slot below, gaps can be closed by taping the board up to the base at the back. A good condition board lets only small whisps of vapour past it. If you do that after getting the block out there's less time for the bees to react and come out the front. So block/mouseguard away, foam in the entrance, tape up the rear then when the varrox is loaded move the foam just enough to get the varrox in from the corner. Then set the timer and turn on.
  • Use a digital kitchen timer, easy to set and reset for 2.5 or 3 minutes and operate the buttons with a gloved hand. The magnet on the back sticks to the hive top and the audible beep allows you to foam the next hive entrance for instance without having to watch the numbers.
  • Run the timer again after turning the varrox off for initial cooling, then varrox and foam out, entrance closed with the block, varrox in the bucket of water and on to the next hive. Remember to reopen the entrance blocks before leaving the apiary.
  • A small roasting tray just fits neatly under the mesh on a Pains poly nuc if you want to treat that box - I have some with 8 frames after cutting out the feeder. Cut a slot in one end of the tray for the varrox handle and tape over the gap above. The land of pounds do one just the right size and you can guess the price.
Just the way I found it worked well operating solo, about 6 minutes a hive once you're going. I use a "jump starter" box (with a better replacement 20 Ah battery). Convenient handle to carry, lighter than a car battery and safer gel rather than liquid acid if you're carrying it. And it has a proper switch. I charge it with a Ctek trickle charger so the battery stays in decent condition. It does batches of ten hives easily, would probably do twice that but haven't tried.
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I have a 12v 12A heavt duty battery charger and my colony is close to a mains power source. Can I connect the Varrox directly to this or must I use a battery of the appropriate power?
If this is a modern battery charger with cut out protection it will not power your Varrox. Modern battery chargers monitor the state of the battery during charges, they usually have 3 stages, start off charge which I think pulsates to break up any deposits in the battery, main charge period, and the final stage is a trickle charge to get the battery up to its full capacity. I would use a battery or power it from your car.
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If your battery doesn't have the capacity you need, and you have mains nearby, then you can use the battery while it's connected to the charger.
That will get around any voltage detection/switching that the charger will do if used on it's own.
the devices appear to spend alot of energy heating the surroundings and the device rather than the oxalic acid which requires very little energy to vapourise 2 gms of material.
Gonna make an interesting conversation if you get pulled over:ohthedrama:

SCENE I A layby in the country

PC Plod: And what are these sir?
BeeK: little foil capsules of acid ...officier
Plod: Acid! are these for your own use?
Beek: No they are for the bees
Plod: have you swallowed any of this stuff today sir?
Beek:No I put in a vapouriser or mix it with syrup

Plod: That a new one,Lets discuss this further down the nick..

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