scope:

Description of Driving Event:

OMRSD S073A.90 thru .230 requires verification of voltages, phasing, and talkbacks to the orbiter. Present talkback verification method for the payload retention latch assembly (PRLA) involves extensive "hot" pin jumpering during testing using a 79K07833 breakout box and test leads. Improper jumper procedure by inserting a jumper at an incorrect location could result in inadvertent shorts or cross connection of live 120 volt and 28 volt electrical lines. This improper procedure could cause PRLA electrical system damage, orbiter interface damage and/or electrical shock/personnel injury.