Cirris CH2 - Building Fixturing for Fast Attach

Traditional Fixturing 27
When to build fixtures
Best practice is to build the mating fixture connecting the device-under-test (DUT) to the tester
before creating the Test Program used for the test setup. Why? If you use Defined
Connectors you can create connector and pin documentation by probing the pins of the
fixture’s connectors while the fixture is attached to the tester, greatly speeding up test creation.
Wiring order of the mating fixture
Fixturing can be wired to the tester in any pin order; however, wiring your fixturing to match the
system point order can save time in the long run. During the test program creation process
you will “attach” your fixtures so that system points are mapped to the fixture points in the
software. If the points in the fixture are in the same numeric order as the tester points,
attaching can proceed very quickly.
Special Requirements
• Fast Attach Connector Types - all connectors using the same Fast Attach Connector
Type must be wired in the same relative pattern to the system pins of the tester.
• Which-end testing (error location) - wires on either side of a connection must be the
same length and preferably as short as possible.
• 4-wire- requires two test points for each point in the mating connector. 4-wire
adapters must be wired in a specific order, see the online manual/help system for
more information.
• Label each system mating connector of the fixture with the name of the Scanner Box
and the 32-pin connector it plugs into. Why? For all test sessions, the connection
path of fixture connectors to specific 32 pin connectors on the tester must be the
same as when the harness was learned or initially created. If you plug the fixture in
differently, you will have to create a new Test Program for that configuration to avoid
getting confusing errors.
Building Fixturing for Fast Attach
Fast Attach is a method you can use to attach (map) connectors by just probing the first pin of
the mating connector as opposed to all the pins as required by the other attachment methods.
All other pins in the connector will be automatically attached so you do not have to probe each
one individually.