For calibration is it required to send back the tester back to the factory or can we run a calibration using our shop standard?

The tester provides a built-in test mode that aims at validating the accuracy of the device by comparing it to a high-accuracy, NIST-traceable polyphase test board or standard. This test is meant to be done in a lab environment and at a rate of one or twice per year, depending on the customer’s guidelines for equipment validation.
Required material
- NIST-traceable polyphase test board or standard
- 120 to 480 V
- 0 to 50 A
- Voltage, Amps and phase angles individually programmable for each line
- Computer (with Windows 10)
- Banana plugs and wiring to connect ST-3/XT3 device to standard (if not socket based)

As there are no moving parts on both units, it’s very rare that the calibration drifts.
Related Articles
How does the ST-3/XT3 work?
ST-3/XT3 : Transformer Rated Wireless Site Tester This unit is a socket type tester, that obtains the reading directly from the secondary of the current and potential transformers. It does not require any external load to perform tests and it is ...
What is the Secondary Burden test?
Secondary Burden test What is the Secondary Burden test? The Secondary Burden test is used to analyze the effect of a resistive burden on the behaviour of the CT. Within the ST-3/XT3 is an array of high accuracy resistors that can be, with the use of ...
For recalibration of the tester, is it required to send back the tester to the factory or can we run a calibration using our shop standard?
Accuracy verification of the meter testers can be done by the user. It is the same procedure that we offer on the NT models and uses the same test jack and interface. The material needed for calibrating the units is: An isolated power supply ...
What is Demand test?
Demand test Ho does it work? The Demand test is used to test meters that have a demand register, (no accessories are needed). The meter must first be configured to be in kW demand test mode (check meter manual for device specific procedure). The ...
How do I update the XT Series tester firmware?
To benefit from all the latest features and bug fixes, Probewell Lab suggests that firmware updates on XT Series testers be performed periodically. The XT Series 2.0.5 & WT Series 2.1.1 Firmware is always available. Watch Firmware Update Tutorial ...