MAC 250s

[zonino]

One thing to remember: try bypassing equipment (i.e. the first mac)

 

I know this sounds simple, but I fixed a "impossible to fix, its been like that for over 2 years" problem in a couple of seconds by bypassing things!

[johnhogg]

Just a thought, I'm sure my mac250's have a mode solely for use with martin controllers, it might be worth checking that it is not set to this mode and indeed all settings on the macs to make sure they're reset, or set to your preference.

 

edit: grammer and clarification

[Just Some Bloke]

Things to check:

 

1) Are you also using dimmers? If so are they getting DMX? If so then the desk is giving DMX. If not then the fault is with either the desk or the cabling between desk and dimmers.

2) If you're not using dimmers then get something else you know to be working and connect it direct to the desk (LED par? strobe? smoke machine?) Either way, you're looking to prove the desk works.

3) Once you know the desk is giving DMX, use the best cable you can find and connect one of the Macs. Do you have DMX?

4) If yes then the cable and the Mac both work. You can go from there, adding one item at a time.

5) If no then change the cable. Do you have DMX? If yes, then your first cable was faulty.

6) If no then change the cable again. Do you have DMX? If yes then both the first cables were faulty.

7) If no then change the Mac. Do you have DMX? If yes than the first Mac was faulty or set wrongly.

8) If you've changed Macs and cables and still no DMX then check the settings on both the Macs and the desk to make sure they're both talking to each other.

9) Are the Macs actually looking for DMX? Have you, in fact, set the address to dAdr (ie DMX address)?

10)Are you're using the second DMX out on the Congo for the Macs? If so have you set the output to Universe 1 or set the Macs to Universe 2 (but not both)?

 

If all of these fail then I'd call the hire company to take a look.

 

Just last week I was called to sort out a problem with some LED battens not working properly - the fault turned out to be 3 different things: one cable, one address problem and one faulty unit. Now that took some fault finding! You just have to stick with it until you've eliminated everything except the problem.

[Ynot]

Hmmm...

 

Unless I've missed it amongst the posts above, the single most common cause of no-DMX is a reversed cable.

Now, I'm making a big assumption here, and that is that the hire co may well have sent the Macs out with 3-pin cables (as is more common than some would believe). From the Congo spec, it (unsurprisingly) sends DMX out on a 5-pin XLR. So presumably IF you're connecting with 3-pin cables, you have an 5-3 adaptor twixt the desk and the first Mac.

 

Now IF this adaptor was supplied by the hire co, then I'd expect it's polarity to be correct, though that's not necessarily a given!

 

But if you're using a 'house' 5-3 cable, then I'd be tempted FIRST to stick a known reversal lead in line to prove that aspect.

 

Other than that, all of the good advice given above still stands. Best bit is to put one mover in front of the desk and cable it with a fresh cable/adaptor and check it works there, then use that as your control item.

[johnhuson]

Unless I've missed it amongst the posts above, the single most common cause of no-DMX is a reversed cable.

 

If it was a reversed cable then quite a lot of fixtures (MACs included) would show that DMX was present via the usual indicator LED but would not respond. As the OP seems to point to the fixtures not showing DMX at all it seems unlikely that it's just a reversed cable. Sounds like a faulty cable but not a reversed one to me.

[Ynot]

If it was a reversed cable then quite a lot of fixtures (MACs included) would show that DMX was present via the usual indicator LED but would not respond. As the OP seems to point to the fixtures not showing DMX at all it seems unlikely that it's just a reversed cable. Sounds like a faulty cable but not a reversed one to me.

I could very well be wrong, but I do recall having NO DMX led lit when sending reversed signal... Haven't had the problem lately, as I usually send 5-pin cables to the first fixture, then whatever's convenient to onward units, as most newer Macs now have both 5 and 3 cokets...

[niclights]

Just to return to a question - no, you don't need to worry about terminating each time when you're trying to eliminate a faulty cable.

 

And to ensure data without relying on the fixture status indicator simply set intensity 100%/shutter open to all.

 

As said before approach all fault finding in a logical manner and it is easy. Go into it randomly and you will get lost and stressed!

 

 

Disconnect output from unit 1 and check. If no response change cable to desk.

 

If works link to unit2 and disconnect output. etc.

[Don Allen]

You have four variables here, ideally you should be looking at one variable at a time.

 

Start at the start of the chain, the desk. Is there a known working DMX device that can be plugged directly into the desk DMX output, without using any of your suspect cables or adaptors? If so this will remove one variable. If you have to, take the desk to a known working dimmer rack to check the desk output.

 

Next step is to test the adaptor if you are using one with another adaptor to get you back to five pin if necessary, testing in the known good combination of desk output and good DMX test fixture. We have two variables or unknowns in this test so it is usefull to carry a set of 3 to 5 adaptors with you that you know are good or borrow a known good set.

 

Once adaptors are tested ok, test your 3 pin cables and mark each one as you test it. Give each cable a wiggle near the plug and socket to look for damaged cable. Test one cable at a time. DMX cable testers are usefull but I got caught out once with an intermittant cable.

 

Finally use your known good desk, adaptor and cables to feed your fixtures.

 

This is not the most time effective way of testing, I have a DMX tester so I would go to the first mover, check the DMX signal from the desk, if not work my way back to the desk via cables, assuming the desk was ok to start with. If DMX present at first mover, use DMX tester in tx mode to check movers along chain from first mover test point. This is the half split rule of trouble shooting, go to the middle, test, go to next middle of faulty half, you are now at a quarter point, test etc.

 

I don't use movers that often so always prep on the ground before rigging, takes a bit extra time but can save a lot of time if something is wrong with gear supplied.

 

Hope that explains the concept.

[Matty93]

Thanks very much for all your help guys, the problem is now sorted! Went through and found the dodgy cable. All the programming on the units was correct so we are now up and running. Thanks for your help