CalCard Calibration Card
CalCard calibration checkbox tool is the size of a credit card and can be used for measuring the insulation resistance and continuity accuracy of electrical test & measurement instruments.
According to the official CalCard® website, CalCard satisfies the ongoing accuracy requirements specified by the IET and is accepted and recommended by regulatory bodies including NICEIC, ECA, NAPIT and ELECSA.
Continuity Range: 0.25Ω, 0.5Ω, 1Ω, 2Ω 5Ω.
Insulation Resistance Range: 0.5MΩ, 1MΩ, 2MΩ, 10MΩ, 20MΩ.
CalCard Pros
- Fits inside a wallet
- Credit card size
- Light and portable
- Compatible with crock clips
- Free downloadable accuracy record
- Electrical Industry Awards winner 2010
How to Test Continuity Accuracy
To check the accuracy of your continuity / resistance tester you need to ensure is the test leads have been set to zero, to do this set your multi-meter or electrical test equipment to the continuity setting.
If your continuity tester or multi-functional tester (MFT) has different continuity ranges, set the range to match the desired test, many digital continuity testers have an auto range setting.
The CalCard calibration card is the size of a credit card and can be used for measuring the insulation resistance and continuity accuracy of electrical testing instruments.
With the correct continuity setting selected firmly touch the probes or crock clips of the test leads together, the test instrument should read 0.00 Ω . If the measurement gives a reading other than zero then the leads need to be nulled.
Download the CalCard user manual.
Null Test Leads
To null the test leads most electrical testing equipment have a null or zero button, this will adjust the test equipment to take into account the resistance of the test leads. Press the null or zero button with the test leads firmly touching each other, the reading should change to 0.00.
Once you have ensured the lead leads are reading zero you can now use the CalCard to check the continuity accuracy of your test kit.
Testing Continuity Accuracy
To test or check the accuracy of your continuity (resistance) tester using the CalCard continuity calibration test card, connect one of the test leads to the common spot on the CalCard calibration card and the other lead on to the 0.25Ω spot, the continuity tester should read 0.25Ω.
Repeat this step for all the other continuity ranges.
If your meter reads a value other than the value you are testing, check your test leads are inserted properly in to the continuity probe sockets on your continuity test meter and you have a solid sound connection to to the Cal card spots.
If that does not make any difference then repeat the process again with new batteries in the test equipment and or with a different set of test leads.
If after trying the options above your test meter is still out of calibration i.e. does not accurately measure the value of the CalCard then your test equipment may need to be re-calibrated by an electrical test equipment calibration company.
How to Test Insulation Resistance Accuracy
To test or check the accuracy of your electrical insulation resistance tester using the CalCard insulation resistance calibration card, set the test meter to the insulation resistance setting and attach one test lead to the common spot on the calibration card and the other lead to the insulation resistance value spot on the CalCard you wish to test.
The meter should read the same value of the calibration card value.
Electrical Test Equipment Accuracy Records
It is good practice to check your test meter for calibration of continuity and insulation resistance before each use, this ensures the measurements you are obtaining are accurate.
As evidence of your ongoing calibration checks it is worth recording your accuracy checks at least every month and keeping a record of such tests with a test instrument ongoing accuracy record.
