Thanks for your reply
Yes it's six scrollers per
PSU, and yes I do have a
return cable.
I think they all shut down at the same time, if not very close to each other.
We have now replaced the 2
PSU's with 4
PSU's and are running 3 scrollers on each, seem to have sorted the problem.
This would be a very strong suggestion that the PSUs were not able to supply the needed
current. If these are single scroll scrollers, they should draw approximately 600 milliamps, when in full movement. That means that a
PSU should be providing 3.6 amps for six scrollers. I would generally suggest at least 4 amps just to be safe. As Scrollers require 24 volts DC, and the fact that DC
voltage will decrease considerably with the resistance of the
wire, long runs of undersizied cable, especially for the first and last cable from the
PSU to the
scroller daisychain could make the
voltage drop. One way to test this, would be to have all of the scrollers on the chain go from the first frame to the last. If they shut down, then try moving just one
scroller on the chain again from front to rear of the
gelstring. If it doesn't shut down, then the peek start up
current of all the scrollers together is dropping
voltage because of the combined
scroller draw and the resistance of the
wire.
I would think that the PSUs should have a large enough capacity, if they were sold with the scrollers. I would check cable runs. If they are long see if there is any way of putting the
PSU closer to the scrollers. Check the cables for broken wires at the solder
point of the
connector. If a few strands are broken, then the remaining strands will create a high resistance, being forced to carry more
current. Also, good
scroller cable should be 14
gauge for the connections on pins 1 and 4. I personally run 18
gauge cable on some 40 scrollers with no trouble, but that doesn't mean that it will work under long runs or underrated PSUs.
I am in communications with Rainbow service department now, it's slow as they only have one english speaking engineer.
I have several of the the very early Rainbow scrollers. They were originated by a company named Camelont in Sweden. Then a
German company took over all of the marketing of the brand. I am not sure if they are still manufactured in Sweden and marketed in Germany, but if so and Camelont will talk to you, there are many more Swedes that speak excellent English than Germans.
The best way to solve any problem of that nature, is to experiment with different connection combinations.
Mark the cables with a temporary number and make notes about what works and what doesn't noting cables, scrollers and PSUs by a number. Then start removing or moving components. Once patterns occur of failures and successes, you can find the problem.
Tom Johnson