Heating elements - voltage control

[mofox1]

Hey all,

I've been thinking about getting a couple of the Camco 3500W low density elements link for my HLT and BK. These look good and seem to have good reviews here there and everywhere...

What I haven't seen much about is using SCR voltage controllers here and here to adjust the temps.

Has anyone had any experience with them?

I like the idea better than putting two elements in (one for ramp), or hanging a hand held one down the side. My alternative is PID control, which I will get to... but I want to get a manual feel for my brewery before I start 'lecking it up too much.

Cheers,
Mick

 

[sp0rk]

Voltage won't let you control the temp directly, moreso it will slow the increase of temp
These work great for still boilers, not so much an HLT or brew kettle (it might work OK for a kettle, I guess)
I'd just stick with a PID

 

[mofox1]

It's mostly for the kettle. I figured at $10 or $20 bucks a pop I could get two! :lol:

Honestly, the pid thing won't happen yet. I've just started AG, and things are going to be manual for a while.

As soon as I start obsessing/playing with PIDs and SSRs I'll want to bring in a pump, and then another and before you know it I'll have shelled out for Nev's full Herms kit. Not that that's a bad thing... It's just that I'd rather not have to sleep on the couch for a week.

Edit: autocorrect screw ups.

Cheers,
Mick

 

[mofox1]

I'd rather not have to sleep on the couch for a week.

On second thought, if that's all it took...

 

[AndrewQLD]

It's mostly for the kettle. I figured at $10 or $20 bucks a pop I could get two! :lol:

Honestly, the pid thing won't happen yet. I've just started AG, and things are going to be manual for a while.

As soon as I start obsessing/playing with PIDs and SSRs I'll want to bring in a pump, and then another and before you know it I'll have shelled out for Nev's full Herms kit. Not that that's a bad thing... It's just that I'd rather not have to sleep on the couch for a week.

Edit: autocorrect screw ups.

Cheers,
Mick

Wouldn't want you to waste your money, I can't see a problem with the voltage controllers you have linked to, they will allow you to regulate the voltage to your elements which in turn will reduce or increase the wattage of your elements so you can adjust the roll of the boil to your satisfaction. Not sure if you might need the controllers to have a bit more grunt though.

 

[dent]

I made the equivalent of one of those for the 3600W element in one of my kettles. It is very useful since at full power the boil can be too vigorous to stay in the kettle, but full power is still available to decrease the time taken to get the the boil. Also saves on electricity cost to some extent.

 

[mofox1]

Any pics Dent?

I'd like to have the control unit on the kettle, but can't think of a way to keep that safe (waterproof). For simplicity sake I'm thinking of a nice long lead to a electrical box containing the unit, a 15A GPO and a short plug.

Also, that way I can just use one unit and/or have one for backup.

Would you prefer one of the ebay links over the other? Only a 200W difference between the two, and while I like the price I'm not sure I could trust 15A to something so tiny as the first one.

Cheers,
Mick

 

[dent]

I'll post a picture sometime when it isn't raining on the way to the shed. I put a sealed enclosure with a 15A IEC socket on the kettle so it is easy to disconnect to clean etc, and the control box is halfway along the 15A IEC lead. The control box is diecast ali and it does get fairly warm. I would want a good heatsink on your controller.

I actually have one of those cheap ones you linked around somewhere, I haven't gotten around to using it for anything yet. The heatsink is probably adequate within the rating of the device, but that doesn't mean it won't get pretty hot.

 

[QldKev]

I used the first one for a while on a smaller element, it worked great. But when I put it onto a 2,200w Keg King element it would not control it, the element just stayed at 100%. I'm not sure why, since the controller is rated to a lot more. In true form the Keg King element blew up, but I have not tried the controller on the new element..

Get your sparky to build a voltage controller using a resistence SSR and a pot, it works a treat with everything I have tried it with.

btw, there is a heat sink mounted behind the SSR

 

[TheWiggman]

That's a great idea dent, I've got a 3600W element too and some control would ideal. Never even thought of it. Please share.
OP to be honest if voltage control was good for managing temps I think you'd see people use them. There are two types of PID - analogue and digital. The on/off digital types used here are simple, reliable and in the scheme of things cheap. Commit to it and you'll spend more time making good beer, and less time fiddling with poorly functioning temp controllers.

 

[mofox1]

I put a sealed enclosure with a 15A IEC socket on the kettle so it is easy to disconnect to clean etc, and the control box is halfway along the 15A IEC lead.

Fair enough, that's a couple less connections than what I was thinking of.

You're confident that the IEC socket on the kettle is water proof enough? That's the main reason I would want a fixed lead to the kettle.

Cheers,
Mick

 

[dent]

Yeah the pins in the socket are moulded into the plastic.

In any event you should always have the kettle, element, and any other associated exposed metal earthed, along with an RCD on the brewery, so if it does happen to leak somehow, you don't find out about it the hard way.

 

[mofox1]

I used the first one for a while on a smaller element, it worked great. But when I put it onto a 2,200w Keg King element it would not control it, the element just stayed at 100%. I'm not sure why, since the controller is rated to a lot more. In true form the Keg King element blew up, but I have not tried the controller on the new element..

Yeah - The contents of this forum is a good reason why I never considered the keg king elements!

Get your sparky to build a voltage controller using a resistence SSR and a pot, it works a treat with everything I have tried it with.

Nice one.

You can even pick up a complete kit at http://www.ebay.com.au/itm/140553985193, although you can still do better by picking the individual components.

Add in a short 15A IEC lead as mentioned by Dent, and this is a nice simple solution for my pre-automation age electric brewery B).

Cheers,
Mick

 

[mofox1]

Yeah the pins in the socket are moulded into the plastic.

In any event you should always have the kettle, element, and any other associated exposed metal earthed, along with an RCD on the brewery, so if it does happen to leak somehow, you don't find out about it the hard way.

Fair enough, sounds good (providing a liberal use of a silcone sealant around the fitting as well). You use a C14 or C20?

Everything is going to be earthed, including the metal trolley/frame/whatever when I get it. And I certainly have a RCD - I had hoped it was regulation these days but so far only WA mandates their use?

When I get around to automating the thing there will be an RCD in the control panel too.

Now I regret giving a bunch of left-over RCD's to a sparky mate a few years back because "I had no use for them". Bah!

Cheers,
Mick

 

[mrsupraboy]

http://www.ebay.com.au/itm/261313519637?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648

 

[spog]

Slightly OT but as a power output control would an electric ceiling fan speed control box do the same job ?
Cheers.....spog.....

 

[TheWiggman]

Wouldn't recommend it spog. The ceiling fans don't pull much power and any 240V water heating element would almost certainly exceed the rating of the fan controller.

 

[JaseH]

What I haven't seen much about is using SCR voltage controllers here and here to adjust the temps.

Yep, I have one on my rig, works great.

I use it to turn the 3600W element down at the start of the boil because the first runnings from the mash only just covers the element - this way I can start bringing it up temp whilst I'm vorlaufing the sparge without fear of burning anything.

I originally got it because I thought the full 3600W might boil a bit too vigorously but its just about right for a 30-40L, so probably not really needed but it does the job well for the price.

 

[mofox1]

Yep, I have one on my rig, works great.

I use it to turn the 3600W element down at the start of the boil because the first runnings from the mash only just covers the element - this way I can start bringing it up temp whilst I'm vorlaufing the sparge without fear of burning anything.

I originally got it because I thought the full 3600W might boil a bit too vigorously but its just about right for a 30-40L, so probably not really needed but it does the job well for the price.

Ah well, I ended up getting the resistance SSR as Kev suggested, but I really should have got one of the SCR ones as I now have to assemble more pieces by hand (and it was a bit more $ too).

Still need an enclosure, heat sink and 15A IEC cable to mutilate.

For now, I'm assuming I'll only need it for my singles. When I start the doubles (which I'm not doing until a get a pump or two) it'll need to be fully cranked. Maybe even with a neoprene/campmat jacket too (or whatever is not going to melt onto my kettle anyway).

Cheers.

 

[mrsupraboy]

The one i posted doesnt need a heatsink. But anyone using and of these I would recomend a cooling fan.


On the one u just bought make sure u have a fan and an anolog voltage controller