Quick Start Guide - DC1000A With Any LCR Meter
The DC1000A precision DC bias current source features unique patented technology that permits its use with almost any manufacturer’s LCR meter.
Using the test leads that were supplied with your DC1000 and with your LCR meter, it is fast and easy to set up your environment to test an inductor under real DC bias conditions.
The same advice also applies to the older DC1000 model.
Set-up and warm-up
As with any measuring equipment, allow both the DC1000A and your LCR to warm up to ensure stable readings.
Consult your LCR meter user manual for suggested warm-up times.
Enable the DC1000A by fitting your interlock system to the Interlock IN port on the rear of the unit, or use the Interlock Override plug provided with the unit.
Open circuit compensation
1 Remove any UUT (unit under test).
2 Try to keep all test leads in the same position as when the UUT is present.
3 Turn the DC1000A ON.
4 Set DC1000A to 0.00A, using rotary knob if needed.
5 Set DC1000A output to ON (press “output” button).
6 Perform open circuit compensation on your LCR meter (sometimes called “Open Correction”).
7 Remember to compensate at all frequencies at which you want to measure.
Short circuit compensation
1 Fit a short between all leads.
A bus bar or thick copper wire is ideal for this, as it will give good contact to all four clips.
Try to keep all test leads in the same position as when the UUT is present.
2 Turn the DC1000A ON.
3 Set the DC1000A to 0.00A, using rotary knob if needed.
4 Set DC1000A output to ON (press “output” button).
5 Perform short circuit compensation on your LCR meter (sometimes called “Short Correction”).
6 Remember to compensate at all frequencies at which you want to measure.
Measuring under load
Once you have compensated the LCR for the leads and DC1000A you can now make measurements under load.
1 Turn the DC1000A output OFF.
2 Add your UUT back into the circuit, attempting to keep the test leads in the same position as when compensating.
3 Select the DC bias current you require using the rotary knob.
4 Enable the DC Bias Current by pressing OUTPUT.
5 Perform measurements on the LCR.
6 Adjustments can be made to the DC bias level while the output is enabled using the rotary knob.
Best practice / Reminders
1) DO NOT disconnect the UUT or LCR while the DC1000 is operating.
2) Always remove the DC bias current by disabling the OUTPUT button before disconnecting either the UUT or the LCR meter.
3) Always try to keep all leads in the same position to improve the accuracy of the compensation, and hence the accuracy of your measurements.
4) For best performance connect the earth socket on the front of the DC1000 with the earth socket on the LCR meter.
5) Consult your LCR meter manual for more detailed instructions on LCR compensation and general use.
If you see intermittent or constant "OVERLOAD" on LCR screen
This is basically a built in protection on the LCR
If it “sees” more than 2V (or 5V depending on your LCR meter model) across its own terminals it reads "overload" or "0.0".
This voltage will be a combination of :
A) AC volts drop - caused by the LCR V AC settings and the resulting AC drop across the UUT (X=2 x PI x F x L)
And
B) DC volts drop - caused by the DC Amps from the DC 1000 and the resulting V drop caused by the DC resistance on the UUT .
Tips
1) Check for good connections as any poor contacts or underrated test leads can give a small contact resistance that could mean bigger V DC at larger Amps.
2) Check the DC R of your UUT is suitable.
3) Check if reducing the LCR V AC reduces the combined V enough to remove the OVERLOAD
4) Check you have ALC (Level control, or similar) =ON in LCR settings