Sorenson DLM16-250EM9E Power Supply

[john sinclair <sinclair@mail.phy.ornl.gov>]

For anyone considering using a Sorenson DLM16-250EM9E Power Supply (serial 
communication option), be advised of the following:

I had problems getting the device to communicate. Initially, I could get no 
response from the device. After examining the section on RS485 communication, 
which notes that S1 (remote/local) must be set to remote, I configured the 
switch so and power-cycled the device. It then responded to one command - but 
only one command. After the first response, the device became silent. 
Repeating the power-cycle gave the same results.

I called Elgar at 11:30am on 6/10/05 and left a message requesting a return 
call.

Elgar did not return my call by 5:00pm so I called back.

I talked with a tech support person and he told me that a line-feed will lock 
up the device and that I should terminate commands with a carriage-return 
only. I asked if he thought this behavior was acceptable and pointed out that 
noise could cause the supply to lock up forever. He thought it was quite 
acceptable.

The serial communication uses SCPI, which is an attempt to standardize the 
protocol. Hopefully, other Sorenson models don't have the same broken 
command-processing engine.

-- 
John Sinclair