Silicone Heater

A Former User

You can use a fuse with a higher voltage rating no problem, they are usually just physically bigger than what would be needed at a lower voltage.

The rated temperature is the temperature at which you want the fuse to disconnect the heater, so it should be above your normal printing temperature and below the temperature you think would pose a fire risk.

jhonf441

Thanks, the fuse must be touching the heater?

dc42

@jhonf441 said in Silicone Heater:

Hello, i have looked for a 110V fuse but I can not find it, my question is if I use a 1800W heater at 110V I could use a 250V to 10A fuse ...

1800W at 110V is 1800/110 amps, which is a lot more than 10A. So no.

Do you really need 1800W? How large is the bed?

gorf26

On mine the heat pad is 330 x 330 110volt

haven't hooked it up yet but working on it now want to be safe...

Thanks gary

mrehorstdmd

@jhonf441 fuses are selected based on current, TCOs based on current and temperature.

An 1800W heater is going to take 16A, so you'd need a fuse rated for at least 20A.

A TCO has to be rated to handle the current you'll be pulling through it, so again at least 20A. They usually self-heat, too, so if you want the bed to operate at 100C you have to get a TCO that's rated for a temperature higher than 100C. Check the data sheet of the TCO for the formula to calculate the TCO operating temperature based on current draw (16A) and your bed's operating temperature.

1800W is a lot of power to pull from a 117VAC outlet. Are you going to blow a circuit breaker?

gorf26

Would this one be OK?

https://www.digikey.com/product-detail/en/SDF+DF152S/317-1136-ND/1014765/?itemSeq=294889851

Thanks gary

Phaedrux

@gorf26 said in Silicone Heater:

Would this one be OK?

https://www.digikey.com/product-detail/en/SDF+DF152S/317-1136-ND/1014765/?itemSeq=294889851

Thanks gary

That looks ok provided you won't be using bed temps of 120c on a regular basis.

Holding Temperature 128°C (262°F)
Rated Functioning Temperature 152°C (306°F)

jhonf441

@dc42
Hello, they are actually 1800/110 amps, but I had calculated 1800 / 250A and approached the commercial value available at 10A so the fuse I find is at 250v, the bed is 600mmx570mm I had already read about 0.4W per square cm but that was according to what I read for beds 4mm thick and aluminum, I have 8mm thick stainless steel, and the reason is that I had enough problems with aluminum, I did not get it was completely flat or curved when heate.
The size of the silicone heater is made to the same extent as the bed.

gorf26

No I use 60°C so should be good then

thanks gary

Surgikill

@mrehorstdmd I just put an AC heater on my printer. I'm looking for fuses and a TCO. Can you point me to any? It's a 110V/1100 watt heater, so I'm thinking 12a fuse.

I'm looking at this for a TCO. A little pricey but seems like it would fit the bill.
https://www.digikey.com/product-detail/en/cantherm/L5015224DELB0XE/317-1557-ND/3135080

Phaedrux

@surgikill said in Silicone Heater:

A little pricey

You might be able to find the same part at a different reseller. Digikey encourages selling in bulk. Check for any regional electronics outfits that may carry them or something similar.

If you're in Canada, check https://www.be-electronics.com/searchresults.asp?Search=thermal+cut+off&Submit=

gtj0

These are the ones I use...
99C : https://smile.amazon.com/gp/product/B07K358CKK/
or
128C : https://smile.amazon.com/gp/product/B0195UX2KA/

sinned6915

Deler-

I have Ali Rubber heater, 800W, 350x350. I know, crazy stupid big, I ordered from the printer BOM before I understand what I do now. Its been great. I honestly don't go over 100C. I know a bunch of people who swear by them and their service.

I dont understand how the Keenvo are better other than their marketing- its a resistance heater with nichrome wires.

suggestions- get it made with a couple of holes for post install thermistor or thermal fuse additions later.

you CAN fix a nicked heater wire by carefully excavating and wire wrapping the ends and covering in RTV.

and dont forget supplemental ground to the bed.

Deler

thanks @sinned6915 I will definitely check Ali Rubber heater