Trouble with Dimmable Ballast

[Harry_Fish]

I have 3 ballast installed in my light fixture

Two work fine but the third shuts down some time in
the middle of the day (high lighting period 100%).

I come home from work and have to go to manual mode
dim it all the way down to "0" for about 10 seconds then
put it back to auto mode and it comes right back on.

Any ideas or do I have a bad ballast????

Thank you

PS: I have checked the wiring 3 times and it is correct.

 

[Matthias Gross]

1. can you make a picture where we can see the whole installation (including the tube sockets)?
2. did you change the tubes from one ballast to another?
3. Does the tube shut down at 100% or at lower brightness?
4. Where is MSHUR to help me here?

 

[Harry_Fish]

1. I could take a picture of the ends but it will not show much since the
brackets obscures the socket connectors. (They are wired correctly).

2. I can flip the tubes around between the ballast if needed but they were
working properly on the old ballast. (the tubes are less than two months old).

3. As it is shutting down in the middle of the day I'm assuming it is in the 100%
part of my lighting curve (they are still in the 100% portion when I get home).

4 Who or what is MSHUR


To add to the mystery I setup the clouds to 25% probability and 25% darkening
over the weekend and the problem did not occur.

I changed it to 15% probability and 25% darkening on Sunday and the
problem came back on Monday

 

[boboxx]

4. his one of the forum member :cP

 

[Matthias Gross]

1 & 2: please do it - I have not other ideas at the moment

reasons for unexpected shut off are:
- too long wires
- wires of different ballasts are to close to each other
- tube is not able to be dimmed (varies mostly from brand to brand, but sometimes there are even differences among the same tubes)
- piece of metal to near to tube, sometimes reflectors cause trouble if they are as long as the tube -> make it shorter
- twisted cable: the ballast manufacturer recommends not to twist the cables between socket and ballast
- ballast grounding not sufficient
....

you see: a picture of the complete setup may help to diagnose what's going on

 

[Harry_Fish]

Thank you for the hints

Let me go through your list and make changes
(ie untwisting the wires)

Is it possible to start including an instruction
sheet with the ballast with this info in it.

It may save the next guy some trouble

Thank you