ScuzZ (Hive Addict)
08-10-03 05:47
No 452707
      Electric Heater Controller  Bookmark   

Swim unfortunately purchased a heating mantle that has a broken heat controller.. It's stuck on high..

Is there a way that swim can control the amount of voltage or amps or something going into the mantle to allow for a range of heat settings?

Swim was thinking about something like those electric frying pan controllers except they won't fit the mantle.. It's lead it like those from a computer power cable.

Any ideas are welcomed.
 
 
 
 
    calcium
(Hive Bee)
08-10-03 17:19
No 452787
      dimmer switch  Bookmark   

Just use an incandescent light dimmer switch. I'm sure this has been covered in the past. Make sure the dimmer is capable of handling the wattage of the mantle.

I got a rotary dimmer and an outlet from the hardware store, mounted them in a water tight 4.5" square electrical box and wired them together so that the dimmer controls whatever is plugged into the outlet. A grounded power cord connected to the box via water tight connection completes the package. The white wire connects to the neutral side of the outlet, the black wire connects to the dimmer which in turn connects to the other side of the outlet. The green wire gets attached to the grounding screw inside the box. Screw on a water tight coverplate and pop the dimmer knob on and your ready to roll with a twenty dollar, spill-proof power supply.

You'll want to get a feel for where to set the dial for the temp you want, and make some marks with a permanent marker.
 
 
 
 
    gottagogo
(Hive Bee)
08-11-03 07:42
No 452916
      If you choose to use a rotary ...  Bookmark   

If you choose to use a rotary "dimmer" type switch, use the one that's made to control ceiling fans.  I believe they are capable of handling significantly more power than a regular light dimmer switch (rheostat).

Arrogance demands respect; Wisdom earns it.
 
 
 
 
    mickyfinn
(Hive Bee)
08-11-03 09:11
No 452927
      TFSE post on VARIAC for mantles  Bookmark   

Here's a bookmark of flippers...

Post 443696 (nthingbutareader: "VARIACs for mantle control", Chemicals & Equipment)

and a thousand guitars sang our national anthem...
 
 
 
 
    ScuzZ
(Hive Addict)
08-11-03 14:13
No 452967
      Solution...  Bookmark   

Swims solution was to add a volume switch from an old television to the power cord.. It's a little dodgy and very dangerous but it works. And as long as it stays away from swims body it'll work just great. Can get the temp close to half a degree..
 
 
 
 
    jimwig
(Hive Bee)
08-11-03 17:25
No 452993
      forget the potentiometer (volume control) or...  Bookmark   

forget the potentiometer (volume control) or if you must ----try it with a load outside on a noncombustible surface cause that baby is gonna get redhot. (its meant for light electronic loads)

also VARIACS are somewhere overrated. I have six of the 10 ampere variety and under the higher loads the brushes try to weld themselves to the copper windings. so derate them or use a larger size - same thing.

on resistive loads (heaters, incandescent bulbs, NOT motors) the cheapo dimmers work well. just keep the load in mind and control it with approipriate size device.
 
 
 
 
    Prince_Charles
(Hive Bee)
08-18-03 04:44
No 454252
      Scuz  Bookmark   

You are pulling my plonker. A heating mantle draws several hundred watts. Any resistive load to control the mantle will need to sink a similar amount of heat. An old tv pot. will just catch fire.

Get a variac lamp dimmer from your local diy store. Mantles are non-inductive loads (unlike motors or fluorescent tubes) and easy to control. El Cheapo dimmers I have seen control 400 W loads no trouble.

HRH The Prince of Wales and Earl of Chester, Knight of the Garter, Rogerer of Servant Girls