|
PrimeMulch
Extreme Sheep Herder



Registered: 03/21/19
Posts: 52
Loc: Lithuania
Last seen: 1 year, 26 days
|
Equate electric heating pad modification.
#26216448 - 09/28/19 03:30 PM (4 years, 3 months ago) |
|
|
Equate heating pad modification. The damn thing kept auto-turning off every two hours.

Unplug the unit. Open the unit up. The triangle safety screw can be removed with a 2.5mm flat head. De-solder the resistor at R11 (the silk screen label for 2H). I removed the resistor by using a pair of tweezers to push on it, while applying heat to each end with a soldering pencil.
 I put some fresh solder on the pads at R19 and soldered the resistor on at the R19 pads (the silk screen label for OFF). Seal it up.
Additional Thoughts/Notes: The unit works by passing the AC from the wall to the mat in cycles of on and off. Turning up the heat on the control has the on time increased. My theory is that you could wire the pad directly to the plug. However, being made from chinesium it may have been made to not melt down/catch fire just because it gets some off time. They may be unsuitable for 24/7 use. I certainly wouldn't trust these pads. Unmodified I don't trust the heating pads anyways. A submersible water heater or a lamp would probably be more safe/reliable.
I was hoping to just cut a trace and have it work, however the chip on the board is a Sonix SN8P2602CSG 8-bit micro controller. In order to have the low medium high work correctly, the resistor must be moved. If the resistor is left off the board, the heat is always on with very short 1< second off periods. The resistor is 1K ohm. I like having the low heat setting work correctly, I figure it reduces the fire risk somewhat by giving the wire some time off.
Edited by PrimeMulch (09/28/19 06:56 PM)
|
the astronaut



Registered: 06/09/11
Posts: 447
Loc: usa
Last seen: 18 hours, 40 minutes
|
Re: Equate electric heating pad modification. [Re: PrimeMulch]
#26221431 - 09/30/19 10:29 PM (4 years, 3 months ago) |
|
|
Sounds kinda crazy no offence. What's wrong with full blast. I've seen though almost everything that makes heat has an over limit switch to break the heater circuit in the event of an over heat situation. You'd have to bypass that to get 24.7 but you'd risk a fire. Leave it alone man.
|
|