Hello Siwarexi,

[snip]

Do you know also how to calculate the accuracy of the siwarex card WP321?

I found this :

d(min(ND))= Delta u min x Emax x N / C / Uexc

C is mV/V of the loadcell I guess...

What do you think about this calculation?

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Split from Accuracy of an FTA-scale.

Hi Siwarexi,

Thanks for you answer ;-)

Herewith the can find the datasheet of the loadcell :

http://www.weightech.com.br/datasheet/hbm-z6fc3-datasheet-b1010-v3.pdf

Model -> Z6FC3 with nominal load of 50kg.

The scale can be use until 60kg (written on the scale)

There is only one loadcell.

Let me know if you need something else ;-)

Monkeyjacob

Hello Siwarexi,

I found another accuracy for this application :

Loadcell = (50 x (1)^1/2) / 3000 = 0,016 kg = 16 gr

   Emax= 50kg  

   Nb loadcell = 1

   Y = 3000

Siwarex card = (0,5 * 50 * 1) / (2 x 4,85) = 2,57 gr

Could you tell what you did?

Thanks a lot,

Monkeyjacob

OK I've fully understood now.

For Y I used the parameter nLC = 3000 on the top of the datasheet. I thought it was the Y parameter.

Thank you for your support

Monkeyjacob

 Hi Siwarexi,

can you explain on the bellow formula to calculate the accuracy.

On the below calculation 

50 = loadcell capacity

(1) = no. of loadcell

^1/2 = ?

11111 = ?

Also on Siwarex

is the 0.5 = Step voltage 0.5 µV/e?

50 = loadcell capacity / nominal load ?

1 = ?

2 = ?

4.85 = ?

MY CALCULATION IS:

Loadcell = (50 x (1)^1/2) /11111= 4.5 gr =5 gr

Siwarex card = (0,5 * 50 * 1) / (2 x 4,85) = 2,57 gr

Siwarexi

Hello monkeyjacob,

Loadcell = (50 x (1)^1/2) /3000???= 0,016 kg = 16 gr

Emax= 50kg

Nb loadcell = 1

Y = 3000 ??? => Y = 11111

MY CALCULATION IS:

Loadcell = (50 x (1)^1/2) / 11111 = 4.5 gr =5 gr

Siwarex card = (0,5 * 50 * 1) / (2 x 4,85) = 2,57 gr

Yes, here you are right. I also got ths value.

Now, you have to use the higher value from the calculations:

5 gr and 2.57 gr.

The higher value is 5 gr.

Therefore the accuracy of your whole scale is 5 gr.

Best regards

Siwarexi

Hi  Siwarexi,

I just need to understand the formula based on the datasheet of the loadcell  discussed here. 

Loadcell = (50 x (1)^1/2) /11111= 4.5 gr =5 gr

Siwarex card = (0,5 * 50 * 1) / (2 x 4,85) = 2,57 gr

Please can you explain each parameters in the above formula. 

Regards,

Subin Sam Mathew