Testhead

4.3        Testhead

The testhead is that portion of the tester that supports the PIN, ASRU and Controller cards.   The testhead is divided into two BANKS and each BANK is divided into two MODULES, see figure 2 below.  Bank 1 contains modules 0 and 1, bank 2 contains modules 2 and 3.  The test fixtures are placed on the banks of the tester and locked down for board testing.  The testhead cards interface to the test fixture through the spring loaded pogo pin “nails” at the top edge on each of these card types.

4.4       Support Bay

The support bay is a stand-alone cabinet that houses the power supplies for the Unit Under Test.  This bay also houses the test station power distribution unit and test station controller on earlier models.

4.5       Emergency Shutdown Switch

The emergency shutdown switch is the large red button located at the lower left corner on the front of the testhead.  It turns off all AC power to the testhead, and is equivalent to turning off the main circuit breaker on the rear of the support bay.  Press the emergency shutdown switch if you ever need to power down the testhead and its associated equipment in an emergency situation.

           CAUTION:     DO NOT use the emergency shutdown switch as a substitute for

correct power-down procedures; i.e., executing the “testhead

power off” command.

Frequent use of the emergency shutdown switch can cause premature failure of the main circuit breaker on the rear of the support bay.

To restore power after pressing the emergency shutdown switch, turn on the main circuit breaker on the rear of the support bay.

4.6        Guided Probe

A convenient holder for the guided probe is provided at the upper corner on the front of the testhead.  When not using the guided probe, store it in its holder.

5.0        POWERING UP THE TESTER

5.1       Locate the tester circuit breakers, they are on the rear panel of the power distribution unit,

in the enclosure mounted to the right hand side of the testhead or in the support bay.  Place the circuit breakers in the “on” position.

5.2        Ensure that the test station controller (Signal Processor Unit, SPU), located in the

enclosure mounted on the left hand side of the testhead or in the support bay, is turned on.

Caution:  On systems with separate SPU and disk drive units, turn on the power to the disk drive and peripheral devices prior to powering up the SPU.  Be sure to allow time for the disk drives to spin up to speed before applying power to the SPU.

5.3        Ensure that the test station monitor and strip printer are both turned on.

5.2        Ensure that the UUT power supplies located in the support bay are turned on.