Texas Instrument 500-2151A

I've had this problem twice with different customers in the last two years. We have repaired a Texas Instrument power supply for them a 500-2151. They plug the power supply into the rack and it doesn't turn on. They send it back under warrenty and I retest it and it seems to work fine. I send it back and it still doesn't work. I came to the conclusion that the problem was that the rack they were plugging it into only worked with a 500-2151A power supply. I can not find out what the difference bewteen the A and non A is. Does anyone know???

The difference is a jumper on the backplane. With the "A" you need the jumper. Without the "A" you need to remove the jumper. We have had to deal with the same issue here. If you need more info I can get it.

Thank you for solving the mystery. Yes can you send me more information about the jumper selection.

Here is the site I use to get manaul for 505 hardware. www.controltechnology.com It appears they are down. The jumper is used on the 500-2151 and is the jumped from the ac to the neutral (there is a sticker on the plastic saying "line in", "ground" and "neutral"). This is on the terminal strip located under the power supply on the backplane. For the 500-2151A no jumper is needed.