KNOWLEDGEBASE

When you are installing the circuit for your new kiln, it is important to use the correct type and thickness of wire. The recommendations provided for each model and voltage variation in the kiln electrical specifications are a good first start. They are a minimum wire gauge to use when running a short distance from your circuit breaker.

1. The specification sheets and web pages have "full load amps," fuse size, and wire gauges associated with each kiln model. "Full Load Amps" is the amount of power needed by the kiln expressed in amps when all circuits are firing and the elements are new.
2. "Fuse Size" is the fuse or circuit breaker size needed to fuse the kiln. This is rated at 125% of the "Full Load Amps" but moves in rounded increments like 60, 70, 80, 90, etc. (note: this is the USA standard, but some countries are different. The extra 25% prevents nuisance tripping)
3. "Wire Gauge" is the wire thickness typically used to connect the kiln to a fused disconnect box. The higher the number, the smaller the wire. NOTE: You may have to increase the wire size beyond 15 to 25 feet of hook-up wire. For instance, let's say you have an e23T that requires a 6 gauge wire, but you have 60 feet from the Circuit Breaker panel to the kiln. The typical way would be to run a 4 gauge wire from the Circuit Breaker panel to a small 60 amp fused disconnect switch near the kiln. Then the wire from that box to the kiln could be the specified 6 gauge.
4. THE SIZE OF THE WIRE IS LIKE THE SIZE OF A FUSE. MULTIPLY THE ACTUAL AMPS GOING THROUGH THE WIRE BY 1.25 TO GET THE CAPACITY NEEDED.
5. An example is that an e23T-240/1P kiln uses 48 full load amps, takes a Number 6 wire to hook it up, and requires a 60 amp fuse (Assuming 60 Deg C wire).

Voltage Drop

1. The wire gauge recommendations in our "Wire Gauge for Connection" specifications on each kiln page are based on relatively short lengths of wire up to about 25 feet. If you have to run wire longer than that you need to take into account voltage drop and upsize the wire accordingly. Voltage drop can significantly affect the performance of a kiln by making less power available to the kiln. This can result in Error 1 issues, slow heating and shorter element life.
2. It never hurts to upsize the wire gauge if you want to err on the side of caution. It is a lot cheaper in the long run to do this while you are running the wire.
3. Here is a voltage drop calculator that can also help you figure out the voltage drop with precision. Click on this link. 
4. Here are some actual formulas for voltage drop.
5. A suggested way to approach this problem is to see what the voltage drop will be for various gauge wires and balance the least amount of voltage drop with the cost of the run. A voltage drop of up to 5 volts is probably OK - but the less the better.
6. A good website calculator for figuring out the size of wire needed to hook up a kiln is wiresizecalculator.net. This will allow you to enter the distance of the wire run, the kiln's full load amps (time 1.25), and the wire's temperature rating to find the wire size you need for longer runs.

Caution: Only use copper wire.

See the below chart for amperage capacities and limits for different gauges and types of wires.  The type of wire affects its temperature rating, affecting its ability to carry more power.

NOTE: The specifications we publish for the kiln assume the worse case of 60 Deg C wire. Depending on the wire type you use, as you can see from this chart, you may be able to use thinner wire.