Heat Mat voltage?

[rob2850]

This may seems like a stupid question but here goes, better safe than sorry. I bought 2 under tank heaters on ebay that came direct from China. I got them because they have a dial on them so I might not have to buy a thermostat. However I noticed on the mat it says 220v-240v, and I thought that normal voltage in a american home was 110v so i wasnt sure if i could actually use them.

[chairman]

110v is standard in the US. Some larger appliances call for 220v. Best guess, your heat mat was probably designed for an European audience... the plug probably looks quite different from normal.

Can you post a link for them? That'll help determine whether it'll be worth your while to make them usable.

[toddnbecka]

You can use them as long as the plug fits, and even if not you can easily replace it. European light bulbs are made for 220 because it's their standard, but will work just fine in US sockets on 110. They will last much longer though, because the filaments are heavier. I can't imagine a heat mat being significantly different, would simply have heavier wire to handle higher voltage, but the wattage would still be low.

[Princess-dad]

If they are rated 220 to 240 thats what you use . I know u wouldn't plug your clothes dryer into 110 120 so no in my opinion either supply 220 to them or replace them . A 220 volt system will have a lower amp draw than a 110 system so to the two different systems will be using different resistances in the heater panels to achieve the same wattage output . If you would like a better explanation look up watts and ohms laws and how they apply. Have a great day sorry for your purchase pay very close attention when buying from china to get correct voltage and plug end and the the proper output centagrade or farinheit s as I have personally miss ordered myself .

[chairman]

Agree with Princess Dad.

There's too much that can catch fire in a heating unit to just plug it in or simply replace a cord cap.

There are several options available to you if you'd like to use them but we'll need more details.

[Princess-dad]

Watts/Volts/Amps/Ohms conversion calculator (http://www.rapidtables.com/calc/electric/watt-volt-amp-calculator.htm)
This link will show you how the wattage of your heat mat will be changed if you use 110 volts instead of the 220 its rated for . Punch in 220 in the voltage space and lets say your mats are rated at 60 watt and 220 volt that gives that mat roughly a resistance of 806 ohms . The omhs or resistance of the matt will stay constant no matter input voltage . So now we know can input 806 ohms and input 110 volts and u will see that a mat with 806 ohms of resistance at 110 volts is no longer rated at 60 watts as it was using 220 volts but 15 watts using 110 volts .I just used 60 watts as a base I have no idea what your matt is rated at but the math holds true no matter the rated wattage u start with . Hope i cleared it up and didn't further confuse .

[rob2850]

Cant link the page so here is the description. I did plug it in but its not very hot. Let this NOMO Anti-creeping Adjustable Temperature Control Heat Mat brings your beloved reptile, amphibian or arthropod warmth conveniently! This heat mat is waterproof and dampproof for long-time reliable use. While, it is not available to water use directly. The adjustable temperature is 0 degree to 35 degree without scale display, so it is recommended to use together with a thermometer. Besides, this heat mat features low power consumption, energy-saving and eco-friendly. It is a useful heat conductor to help adjust temperature. Safe and balanced temperature is very beneficial to tortoise, snake, lizard, gecko, spider, etc!
Features:
1. Anti-creeping and temperature adjustable
2. Waterproof and dampproof for reliable use
3. Grid structure ensures excellent and even heat dissipation
4. Safe and balanced temperature distribution, automatic temperature control
5. With a adjustable switch
6. Easy to wash, convenient and practical
Specifications:
1. Brand: Nomo
2. Material: Plastic
3. Color: Black & Transparent
4. Power: 5W/7W/14W/20W/28W
5. Voltage: 220V-240V
6. Waterproof: Yes
7. Dampproof: Yes
8. Adjustable Temperature: 0-35℃
Package Includes:
1 x Heat Mat

[chairman]

You'll probably want to get a "travel" converter to run the pad.

You might find this guide helpful:
How to Choose Electricity Adapters, Converters and Transformers - REI Expert Advice - REI Expert Advice (http://m.rei.com/learn/expert-advice/world-electricity-guide.html)

[Dan84]

Lets assume you bought a 1000W heating pad.
A typical heater is just a length of filament with a given resistance.

Power = current * voltage
current = power / voltage = 1000W / 220V = 4.5A

Resistance = voltage / current = 220V / 4.5A = about 50 ohms

The resistance value is fixed
So the current of the heating mat at 120V would be

Current = Voltage / resistance = 120V / 50 ohms = 2.4A

And finally

Power of mat at 120V = current * voltage = 2.4A * 120V = 288W.

So with something as basic as a heating mat there is no danger to plugging it in to a lower rated voltage, but you are only heating at 25% of its intended value.

Hope that helps.