Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

How to calculate temperature coefficient

Status
Not open for further replies.

hemnath

Advanced Member level 3
Joined
Jun 24, 2012
Messages
700
Helped
61
Reputation
120
Reaction score
57
Trophy points
1,308
Location
Chennai
Activity points
6,566
Hi,
I have a pressure calibrator and I opened to check the sensor. It is Meas sensor 89CV.

On the sensor datasheet, its temperature data's are,
Temperature Error – Span -1.0 %Span
Temperature Error – Zero - 1.0 %Span
Thermal Hysteresis – Span ±0.05 %Span
Thermal Hysteresis – Zero ±0.05 %Span
Compensated Temperature Range -20 +85 ºC

But in their product datsheet, it is mentioned as,
Temperature coefficient ± 0.005% of reading / °C with respect to 20°C
Operating Temperature 0 to 50°C
Calibrated Temperature 20°C ± 2°C
Calibrated Temp. Range 0 to 50°C
Storage Temperature -20 to 70°C
Temperature Effects 0.001% of reading /°C between 0 to 50°C

When I try to calculate using sensor datasheet,
1%span = -20 +85 ºC
1% span = 105ºC
1 ºC = 1%span/105
1 ºC = 0.009% span
Is this calculation is correct for calculating temperature coefficient?

Could you please explain how to calculate temperature coefficient and temperature effects?
 
Last edited by a moderator:

KlausST

Super Moderator
Staff member
Joined
Apr 17, 2014
Messages
23,032
Helped
4,716
Reputation
9,448
Reaction score
5,089
Trophy points
1,393
Activity points
152,591
Hi,

Span: -20°C ... 85°C = 105°C
So 1% span = 1% × 105°C = 0.01 x 105°C = 1.05°C

Klaus
 

hemnath

Advanced Member level 3
Joined
Jun 24, 2012
Messages
700
Helped
61
Reputation
120
Reaction score
57
Trophy points
1,308
Location
Chennai
Activity points
6,566
Thanks for your reply. The point is not clear for me. Sorry.
 

d123

Advanced Member level 5
Joined
Jun 7, 2015
Messages
2,502
Helped
494
Reputation
992
Reaction score
525
Trophy points
1,393
Location
Spain
Activity points
27,127
Hi,

Not sure if tempco method valid for this...
+-0.005%/°C might mean that moving away from 20°C ambient or device junction temperature it adds the ppm (tempco) error.
+-0.005 * (50°C - 20°C) = +-0.15
1 - 0.15 = 0.85, 0.85 * 50°C = 42.5
1 + 0.15 = 1.15, 1.15 * 50°C = 57.5

Or maybe under 20°C it is -0.005% per °C and over 20°C the error is +0.005% per °C.

Not sure, I could be completely wrong. Datasheet might have a box method graph to show expected error curve or 's' shape across temperature range under their test conditions.
--- Updated ---

Datasheet would help a lot.
 

Akanimo

Advanced Member level 3
Joined
Aug 30, 2016
Messages
790
Helped
136
Reputation
272
Reaction score
144
Trophy points
43
Activity points
5,419
Hi,
Hi,
I have a pressure calibrator and I opened to check the sensor. It is Meas sensor 89CV.

On the sensor datasheet, its temperature data's are, ...
🧐
But in their product datsheet, it is mentioned as,
Please post a link to this datasheet.
When I try to calculate using sensor datasheet, Is this calculation is correct for calculating temperature coefficient?

Could you please explain how to calculate temperature coefficient and temperature effects?
I would be expecting some pressure numbers here though.
 

dick_freebird

Advanced Member level 5
Joined
Mar 4, 2008
Messages
8,117
Helped
2,272
Reputation
4,554
Reaction score
2,293
Trophy points
1,393
Location
USA
Activity points
64,900
What the tempco -is-, and what the tempco
"could be and still get shipped" are loosely related.
The latter pertains to WCA but isn't going to tell
you anything about one piece in hand necessarily.
Other than, it should be better (how much, is not
said unless you paid for detailed test data pack
which is not really an option outside MIL / aerospace
product grades with their heinous pricing, to which
the data pack is always another lot based upcharge).

Some sensors have nonlinearity (bowing) which
will make an end-end tempco lower than tempco
measured near either end and higher than in the
middle.
 

Akanimo

Advanced Member level 3
Joined
Aug 30, 2016
Messages
790
Helped
136
Reputation
272
Reaction score
144
Trophy points
43
Activity points
5,419
What do you want to do - to determine the adjusted pressure from representative measured voltage?

Actually, the sensor is already partially compensated for temperature effects.
 

Akanimo

Advanced Member level 3
Joined
Aug 30, 2016
Messages
790
Helped
136
Reputation
272
Reaction score
144
Trophy points
43
Activity points
5,419
To be able to obtain temperature coefficients, both of zero and of span, you would need to have measured voltage data for both minimum and maximum pressures at maximum temperature Tmax, assuming that those presented in the datasheet would be for ambient temperature.
 

Akanimo

Advanced Member level 3
Joined
Aug 30, 2016
Messages
790
Helped
136
Reputation
272
Reaction score
144
Trophy points
43
Activity points
5,419
For the sake of one that might reference this thread in future:

...assuming that those presented in the datasheet would be for ambient temperature.
By this I meant 'if you thought that those presented in the datasheet were for ambient temperature'.

Unfortunately, I am not a native English speaker.
 
Last edited:

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top