accuracy of NI 9265

[siva0182]

https://www.ni.com/en-us/shop/model/ni-9265.html

I have been considering the NI 9265 module for a constant current source of 1mA.

The specs for this module says range is 0-20 mA and range is 0.13 mA.So if i am using the module for a constant curent source of 1mA what could be the error involved or what is the accuracy of the current value.

Will the actual vlaue lie between 0.87 -1.13 A or 0.99-1.001mA?

[KateB]

I don't see anywhere mentioned about 0.13mA range, but refer to its accuracy on page 13 of http://www.ni.com/pdf/manuals/374067e.pdf, for 1mA, a deviation can be up to 1*.0025+20.6*.004=.0849mA.
Therefore, the current should be in 0.9151-1.0849mA

[siva0182]

yes true The calculation you have done is correct.But Now I am wondering if I need to use a 1mA constant current to measure the diode voltage with an accuracy of 0.1mV  is it worth using this module or are there any other alternatives?

regards

Sivanand Somasundaram

[KateB]

Try USB-4065, http://www.ni.com/pdf/products/us/cat_NI4065.pdf.

DMM is specifically designed for diode testing.

[siva0182]

I may be buying a high speed tmeperature measurment module Ni9213 as below 

https://www.ni.com/en-us/shop/model/ni-9213.html

 along with Compaq DAQ.

https://www.ni.com/en-us/shop/category/compactdaq-chassis.html?productId=118191

So I am not sure if the DMM you are suggesting will fit in the form factor I am considering..

Moreover 4065 is only a DMM .But i need to source a 1mA constant current.

[KateB]

USB-4065 is not for CompactDAQ, but it's probably the best option, if you wish to measure diode with USB interface.

However, if you confirm that you wish to use 9265 with CompactDAQ, then accuracy is a trade-off.

[siva0182]

YEs true.But from my understaning  USB 4065 can not source current which is one of my requirements.

[KateB]

If 1mA source is just for diode measurement.

4065 source the current out when measuring diode for you, but if you need it for other puirpose, then you need a current source module.