high temp withstand sensor

1. Sensor to sense what ? - if it is to measure the temperature, you may look (via spectrography) at the wavelength of the object's glow, and calibrate to a set of relevant degrees.

2. Physical switches for electrical currents, or "a switching system" per-se?

3. Are those suppose to operate within the 1000 deg cel environment, or only in proximity to?

Hello Guest,

While some limit switches and proxy sensors may work at those temperatures for a short time, in the longer term they will fail.

The internal components will be overheated, along with the wiring needed to couple to instruments and controls.

As Yuval above has suggested, for long-term rel\liability, you need optically coupled controls.

Have a look here at Globalspec, for a fine place to look for what you need: http://search.globalspec.com/productfinder/findproducts?query=high%20temperature%20sensors%20switches

If you are still needing further advice, reply here with thank you.

Kind Regards....

I have seen a smelter using industrial switches with either water or air cooling combined with insulation from the immediate environment. Ask your furnace equipment supplier for advises.

What would you like to sense by the proxy sensor.Will it be exposed to 800-1000 deg on a continuous basis or it will be momentary.Do you want to use the limit switches for closing/opeing /positioning etc near the high temp zone during forging application.What will be vibration levels at the place of installion.You may write to enpee_2003@yahoo.co.in or call at 91-9329009399

This all depends on where you are putting the prox switch. I work on Aluminum remelt furnaces and we constantly have problems with prox switches melting. This usually occurs because the cooling system fails or the furnace pressure goes wonky. I agree though, need more information on how you are using the prox switches.

I will supply this though.... if the switch is small, plastic, or cheap, you probably don't want to use it.

There are sensors withstanding extremes in rocketry (NASA), very reliable, with prices equally astronomical.

Seriously, just to take a proximity sensor. If I have to sense the proximity of a full / empty ladle or a hot slab ready to be rolled, infrared / ultrasonic come to mind. In that high radiative heat environment they will not survive without active cooling. Heat pipes may come handy to separate the board from the cooling. If you want to monitor your roller's axle for runout, inductive sensor in cofired ceramics or quartz coating comes to mind. But in any case, it is a bitch for sure.

"we are worlds top most forging industry"

If you are the largest forging industry why do you need information on limit switches? Also, you still haven't said what you are going to do with these limit switches. Are you going to try to put them in a molten metal bath? For our own aluminum remelt operations, which get up to around 2300 degrees F in our furnaces (not the metal temperature, the air temperature to melt the metal), the only direct sensor readings we take are for temperature in the furnace flue, roof and bath. Everything else is done without putting electrical equipment into the fire as it were.