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E

Enzo

Jan 1, 1970
0
If a load cell has a bridge of strain gages with sensibility of 2 mV/V, and
I apply a V=5v, and the range of force is from 0 to100 Kg, is correct to
say that with the max force applied the V difference should be 100 * 5
*2mV/V = 1V ?
 
P

Paul Burke

Jan 1, 1970
0
Enzo said:
If a load cell has a bridge of strain gages with sensibility of 2 mV/V, and
I apply a V=5v, and the range of force is from 0 to100 Kg, is correct to
say that with the max force applied the V difference should be 100 * 5
*2mV/V = 1V ?

Nononononono unless it's given as 2mV/V/kg (which it isn't)

The output at maximum load will be 2mV * 5 = 10mV.

Paul Burke
 
P

Pooh Bear

Jan 1, 1970
0
Enzo said:
If a load cell has a bridge of strain gages with sensibility of 2 mV/V, and
I apply a V=5v, and the range of force is from 0 to100 Kg, is correct to
say that with the max force applied the V difference should be 100 * 5
*2mV/V = 1V ?

Force is correctly measured in Newtons ! To use the old fashioned way of
talking ... 1 N = 1 kgf ( not 1 kg ) = 1kg*9.81m/s. F = ma. Check the
sensitivity spec.

Other than that, your calculation seems ok

Graham
 
J

John Larkin

Jan 1, 1970
0
Nononononono unless it's given as 2mV/V/kg (which it isn't)

The output at maximum load will be 2mV * 5 = 10mV.

Paul Burke


Right. You only get millivolts out of these things.

John
 
J

John Fields

Jan 1, 1970
0
If a load cell has a bridge of strain gages with sensibility of 2 mV/V, and
I apply a V=5v, and the range of force is from 0 to100 Kg, is correct to
say that with the max force applied the V difference should be 100 * 5
*2mV/V = 1V ?

---
No. What the 2mV/V means is that for every volt of excitation, the
bridge will output 2 millivolts with the maximum rated mechanical
load on the load cell. Like this:

k Vin Fin
Vout = -----------
Fmax

where k is the rated sensitivity of the load cell in mV/V
Vin is the excitation voltage
Fin is the force exerted on the load cell
Fmax is the load scale's full-scale force rating


In your case we'll have:

2mV
----- * 5V * 100kgF
1V
Vout = -----------------------
100kgF


which, after the V's and the 100kgF's cancel out leaves you with:

Vout = 2mV * 5 = 10mV
 
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