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Rob,
It does, but the maximum operating temperature is 200°C for the 4148. With ~-2mV/°C tempco, it is difficult to build a controller that works well up to that temperature. You also need to calibrate it because the tempco is not constant over the full temperature range, nor is it exactly -2 mV/°C. I was unhappy with the way it worked when I did it, so I switched over to the RepRap thermistor. Unhappy with the poor performance at hot temperature, I bought the thermocouple based temperature controller.
The linearity of diode type temperature sensors is pretty good for short temperature ranges, but going from room temperature to the temperature ranges we are using didn't give me satisfactory performance.
For me, the thermocouple is the best route. Thermocouples are tricky because their terminations make additional thermocouples in series with the measurement couple, screwing up the readings. A packaged solution that takes care of the termination issues is the easiest way. At $8.99, a bargain! No fuss, no muss, no bother. And digital readout, too.
Harvey
Always learning something new here.
1N4148 + LM741 makes a temperature sensor
On 01/01/2017 07:11 AM, 'David C. Partridge' david.partridge@... [Homebrew_PCBs] wrote:
It’s a Vivid IP-330 described as having “hot roller” technology.
I need to dig it out as I can’t remember what I did to increase the Temp range (probably just changed a resistor in the op-amp circuit that used a 1N4148 as a Temp sensor).
Can’t find a parts list …
From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: 31 December 2016 18:11
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Re: Temp upgrades of lam's HOW high is high heat conditions
Really? This grabs my attention.
What make and model?
Can you take a picture and share?
Is there an online parts list we can eyeball that shows how concentric heaters are mounted?
On 12/31/2016 11:53 AM, 'David C. Partridge' david.partridge@... [Homebrew_PCBs] wrote:
But, but the heaters are concentric with the rollers (or at least they are in my laminator) so
stopped/forward/reverse should make no difference.
Dave