# Temperature Measurement System

Discussion in 'Homework Help' started by LennonConnor, Dec 1, 2012.

1. ### LennonConnor Thread Starter New Member

Dec 1, 2012
2
0
Hi All,

I'm just looking for some assistance with regards to a coursework I have (For info I am mechanical so its confusing the hell out of me!). Basically I have a Wheatstone bridge with a Platinum RTD. In turn this is coupled up to a 3 Op Amplifier (well I have chosen to couple up to it). One of the questions state "Calculate the gain required to match the output of the bridge with the input of the amplifier". So I have the following: Vinput = 10V R1=100Ohms R2 = 100 Ohms and R3 and R4 are 3557.67 Ohms. The range of the output signal is 0 to 100mV and it is to measure from 0 to 100 degrees.

Am I correct in thinking that this is the difference between the input voltage and the output or the amount needed to turn 100mV into 10 volts through the amplifier or am I completely off the beaten track! This would mean we need an output of 10V and there is an input of 100mV so the required gain is 100??

Thanks for any help.

2. ### crutschow Expert

Mar 14, 2008
13,501
3,375
If the bridge output is 100mV full-scale then yes, you need a gain of 100 to achieve a 10V full-scale output.

3. ### LennonConnor Thread Starter New Member

Dec 1, 2012
2
0
Thanks for your help it is much appreciated.