The Lighting Controller

Hi,
I've been using and installing ShowXpress since it was introduced as one of the top (and only) lighting professionals in my area.
Recently, I sold and installed an Xpress 100 for a church in and have been back 6 times for issues.
The software is ver. 8.2.28 and is installed on a Dell notebook PC running Win 7 Professional.

So far, I have tried 2 different Xpress 100 interfaces and both are experiencing the same issues (1 worse then the other).
The problem seems to be a weak signal.
There is 50 feet of dmx cable from the interface to 2 Chauvet D-6 dimmers (3 foot jumper between the 2 dimmers) and 125 feet from the dimmers to the stage where it plugs into 1 Chauvet Color Strip LED wall wash fixture.
I can't seem to make the whole system work together with a stable dmx signal.
I can use either the dimmers, or the LED but not both.
With all fixtures online, there is no control. Dimmers flicker and flash and the LEDs also flicker and flash randomly.
This happens regardless of weather the LED is connected to AC power or not and I have inserted my personal iso split with each leg on separate outputs so it CANNOT be a ground loop problem with the LED.
When the dimmers are bypassed, the LED fixture works but flickers to full on every 20 seconds or so.
When the LED fixture is disconnected, the dimmers work fine.

I have tried everything I know from my 20+ years of experience to fix this:
- Installed all new DMX cables.
- Tried an end of line terminator (resistor).
- Optically isolated each output leg.
- Tried different Xpress 100.
- Checked PC drivers.
- Tried different PC.
- Tried different LED fixtures.
- Powered fixtures from different circuits.
- Tried an Xpress 512 interface.
- Tried my X-factor interface.

I am completely stumped.
I cannot bill this customer for any more time so now I'm working for free to solve these problems.
Any help would be appreciated.
PS your ground loop topic link no longer exists and I can't see it.
I would like to explore the possibility of ground loop issue with the dimmers on my visit tomorrow.
Can you please include the ground loop solution in your reply?
Thank you.

Borrow a DMX splitter/Booster and try inserting it: here I solved some issues this way (not only with ShowXpress BTW)

Mayby the power of the notebook is 2 weak
Try rhe d512 in standalone with external power

Hello guys and thanks for the ideas.
I'm now leaning towards the AC power in the building as the cause of the problems.
This equipment was in another building, then moved to this one.
The only common denominator is the AC power.
It is 3 phase AC feeding the panel. There was an issue with the 3rd phase dropping shortly after they moved in.
Florida Power and Light solved that problem but I do remember them speaking of a lightning strike as the cause.
We suffer from alot of lightning here.
Because the earth in this region is mostly sand, your typical ground rod only needs to reach the water table.
But if it suffers a strike, the portion of the rod in the water table becomes coated with glass due to the super heat associated with direct and near-direct strikes.
Sometimes, this creates issues in the building the most dangerous being GFCI failure.
I am not a licensed electrician, but I am an ME in live production and understand both AC and DC electrics on theoretical levels.

As FL building code dictates, each time a commercial or high-occupancy building changes tenants, an inspection is ordered to renew the license of occupancy.
Fire and electrical inspections are large parts of the criteria for passing these inspections.
So, as an installer, I am assuming the power is safe and stable.
Seems assuming might be my mistake.
I plan on fully testing the integrity of the electric I am using in the venue and report back.
Thanks again.

You may be on the right path, but I was just wondering if you have a termination plug on the last fixture of your run?

Bob