Nichrome Wire Calculator
- Issue - above calculator does not fix voltage
- Select convenient length
- Select max temp - such as 550C = 1000F
- Match gauge to proper voltage drop of 120V
- Find out max gauge that is within current limits (15A) and has correct voltage
- Limit for 15A outlet is 1800W
- Remains within 15 amps
- Shows correct voltage
- Max temp - select it to match voltage - you determine max possible temp and judge whether it will burn out your system if you have temperature sensitive components
- Note that Gauge 17 is the max fatness that stays within 1800W
- Note: 22' of 18 ga gets us right at 120V, and 1560W. Good. But temperature of 1260F is a little high.
- 12' of 26 ga draws 450 Watts.
- This was acceptable, but burns out thermistors if placed directly on heater.
- Point: the shorter the nichrome, the hotter it will get while remaining at the correct voltage
- Keep conservative on the bed power,then.
- For same power density on large bed (7W/sq in), would need 4000W of heat. Can't do that. Limit is 1800W. the question is how best to achieve it - what length of nichrome is required for a workable length, while keeping temperature lower rather than higher.
2x2 foot bed
- 1800W limit
- To cover bed - try 6 lines separated by 4" of space. This means 12' + 2 feet return or 14' of sleeve
- Gauge 17, 28' long, gets max 1090 and 1570 watts
- sleeve it in 14' of sleeve. Quite doable. needs total of 28 feet of sleeve.
Shorten it by 2-4 feet to get max power and temperature.