DCCT and Daughter Card

​Selection Guide

How to Select DCCT and BiRa Systems Daughter Card

Selecting the DCCT:

Go to the GMW Associates website Danisense Current Transducers Tech Support page to view the DCCT datasheets:

https://www.gmw.com/electric_current/Danisense/DS-Support.html

Generally, the DS200ID through DS600ID models with current (not voltage) outputs will be appropriate. The 3 digits after the DS describe the nominal AC current, you will be interested in the nominal DC current which is 1.5 times the nominal AC current.

Note: The “ID” after the 3 digit current capacity indicates current output. Voltage output models are indicated by “UB” and cannot be used with the BiRa Systems daughtercard. 

Select a model with a nominal DC current which is large enough to handle the current output of the system power supply.

Selecting the BiRa Systems Daughtercard:

Find the Primary/Secondary ratio (turns ratio) in the DCCT datasheet, for example 1:1000. Divide the maximum power supply current by the larger number of the turns ratio to determine the maximum secondary current of the DCCT. This is the current which will be flowing through the daughtercard.

If this current is less than 200mA, select the 200mA daughtercard.
If this current is between 200mA and 400mA, select the 400mA daughtercard.
If this current is greater than 400mA, a DCCT with a larger turns ratio will be required. 

Example:
 
For a 250A power supply, the DS200ID has 300A of nominal primary DC current. With a turns ratio of 1:500, the secondary current is 500mA (250A/500 = 500mA). This is too much current for the daughtercard, so a different DCCT must be selected.

The next higher model is the DS300ID which has 450A of nominal primary DC current. With a turns ration of 1:1000, the secondary current is 250mA (250A/1000 = 250mA). This current is between 200mA and 400mA, so the 400mA daughtercard will be selected.