Some of Pickering Interfaces products provide a calibration port, mainly on programmable resistor modules, which has a number of potential uses.
- It can be used to simplify calibration of the module or device if regular calibration is required. A multiplexer allows the calibration device (usually a DMM) to be connected to each channel in turn without having to change the wiring connection enabling the results of the calibration to be recorded in the calibration tables.
- It can be used in the test system to check that the device has been set to the correct value, for example resistance in the case of a resistance simulator. In this case the device disconnects the load from the selected channel so that a test can be performed without having to disconnect the UUT.
- To support adjustment of a module or device by providing access to the internal connections of the channel for the purpose of changing its calibration file. In this case the module may access parts of the channel the user connection does not provide access to. Where a calibration process indicates that adjustment is needed this should normally be done by Pickering Interfaces with factory supported software and tools, the precision resistor modules in particular use high stability resistors and changes may indicate that something has changed in the module that requires factory attention.
The calibration port maybe on a separate connector or it maybe on a connector that is shared with the other user connections. The use of a separate connector is the most flexible arrangement, but it is not always possible to provide a separate connector because of space restrictions.