440 Volt heater

[TreeKiller]

Not a gun related project but I have a 7 inch SS tube 16 inches high that I use to melt bees wax in for dipping candles. I was looking for a band heater to put on it but the only one i could find was a 440 volt 1900 Watt. if you ran it on 220 would you get 1/2 the watts and heat? I want to hook it up to a PID and only go to 145 to 160 F

Thank you

[smoked turkey]

TreeKiller: I believe the power would be cut to one-fourth, or in this case 475 watts. The current calculated to be just over 2 amps at 220 volts. If you have an ohm meter you might check the resistance. It calculated to be about 100 ohms. If it is then these calculations are pretty close.

[Dale in Louisiana]

In my real job we quite often specify heaters for 240 volts and run them at 120. When you cut the voltage in half, you cut the watts by the square of that. That's Basic electricity 101.

A half times a half equals a quarter. If I use a 240 volt, 1000 watt heater and feed it with 120 volts, I get 250 watts.

Why would engineers do such a thing? We're putting these heaters in some pretty inaccessible spots and when you cut the voltage, the heaters last forever (almost).

dale in Louisiana

[deltaenterprizes]

Agree with the posts above

[pull the trigger]

Is the 440 volt not 3 phase?

[TreeKiller]

Yes it is just 440 volt.
Thanks for all the replies. Now just have to figure how long 475 watts wili take to heat up the wax.

Thanks to All
Dan

[fresch]

440 volt (480v, 460v) can be 3 phase three wires or single phase 2 wires; phase to phase, 270v phase to ground.

[bangerjim]

Phase had NOTHING to do with resistive heaters. Only inductive motor loads.

bangerjim

[sparkz]

Heats a resistive load just divide, and watch the cable & fuse or breaker size
(As voltage goes down amperage goes up)

Patrick

[Dale in Louisiana]

Phase had NOTHING to do with resistive heaters. Only inductive motor loads.

bangerjim

Not to be too argumentive, but I've been in industrial high power (and high voltage, but this ain't THAT) electricity for almost forty years and there are definitely three-phase, 240 and 480-volt heaters, some integral, built from the factory, some assembled from carefully connected single-phase units. I have connected then both delta and wye, and they NEED three-phase to produce rated output.

I've used three 277-volt units, connected wye, to make a three-phase 480-volt unit, and used three 480-volt single phase units connected delta to make a 480-volt unit. Both these configurations will produce SOME heat with single-phase 480, but not nearly what the three-phase unit will do.

Frequency has nothing to do with resistive heater loads, only inductive loads.

dale in Louisiana

[Dale in Louisiana]

Heats a resistive load just divide, and watch the cable & fuse or breaker size
(As voltage goes down amperage goes up)

Patrick

Nope, not exactly.

Let's say you have a 480-volt rated heater that's good for one amp of current. One amp times 480 volts gives 480 watts. The resistance is 480 ohms.
That's basic Ohm's Law: Watts equals volts times amps. Resistance equals volts divided by amps.

Now, let's take that same heater and put half voltage, 240 volts through it. The resistance hasn't changed because that's a physical property of the way the heater is built, so it's still 480 ohms. with 240 volts on it, only a half an amp will push through. Again, Ohm's Law: Amps equals volts divided by resistance. 240 divided by 480 equals 0.5.

So what does that do to heat? Ohm's Law again. Watts equals volts (240) times amps (0.5) and that gives us 120 watts. Cutting the voltage in half on a fixed resistance gives a QUARTER of the heat.

Now, back to Patrick's statement. If you WANT the same amount of heat at half voltage, then amps MUST go up. This is usually accomplished by either of two methods. First, you manufacture an element with lower resistance, or second, you connect several high resistance elements in parallel, giving more paths for current, each element contributing to the overall heat load. Both these methods are commonly used.

dale in Louisiana

[bangerjim]

Bottom line........just buy the right heater for the electrical service you have available!

And do not mess around with salvage crapola. Life's too short.


bangerjim