# How does temperature compensation work for strain gauge in wheatstone bridge

Wheatstone bridge is used for temperature compensation for strain gauges

If 2 strain gauges are connected like this figure. Due to temperature variation; the resistance Rg will change in the same way.

Lets say; the bridge is balanced at start. R1/R2 = (RG+DeltaR)/(RG-DeltaR)

If strain gauge resistance increases due to temperature: R1/R2 = (RG+DeltaR+RT)/(RG-DeltaR+RT)

How does this compensation work?

(RG+DeltaR+RT)/(RG-DeltaR+RT) is not the same as (RG+DeltaR)/(RG-DeltaR)

So gets the bridge unbalanced???

• You would need also R1 and R2 to be strain gauges. Commented May 10, 2018 at 21:38
• It's said, that half or full bridge includes temperature compensation. This is half bridge.
– Kono
Commented May 10, 2018 at 21:43
• Where is this said? Commented May 10, 2018 at 21:55
• But first of all make your equations in the form like used in this forum. At least put the brackets, since the math, rules say multiplication and division have a priority over subtraction and addition. Commented May 10, 2018 at 22:01
• elektron.pol.lublin.pl/elekp/ap_notes/… - Page 3-4
– Kono
Commented May 10, 2018 at 22:03