Mac 700

[techtech]

Hi All,

 

We are using 6 mac 700's on a show. 4 of them on LX 1. I had to swap out unit 1 due to a faulty colour wheel. The unit that I changed it with after a while during the performance will not go to its programmed positions. After some experimentation I discovered that taking control of all the macs on LX 1 at the same time and moving them around via the roll ball (520i desk) the unit went out of sink with the others and when I told them to go to a home group the tilt on the unit was at maybe a 35 degree angle.

I checked that all the setting were the same as the unit that was taken down.

 

PSET 16EX

Studio mode OFF

Swap OFF

Pan Invert OFF

Tilt Invert OFF

Enable DMX reset ON

 

The Pan and tilt Calibration levels are set to 128.

 

Has anyone got any ideas on how to sort this or do we recon I wait until another replacement is sent? A couple of days.

 

Any help would be much appreciated.

Merry Christmas and thanks

 

 

TT

[Ynot]

Usual questions:

 

You say the personalities of all 4 Macs are the same on the fixtures - Have you checked that this is the case on the desk? eg is that fixture 16BT not 16 BT EX?

 

Have you tried swapping the DMX address of the faulty unit with one that works?

 

Have you checked the cable twixt the faulty unit and the previous one? (Though if the dodgy one isn't at the end that is unlikely to be an issue)

[techtech]

Usual questions:

 

You say the personalities of all 4 Macs are the same on the fixtures - Have you checked that this is the case on the desk? eg is that fixture 16BT not 16 BT EX?

 

Have you tried swapping the DMX address of the faulty unit with one that works?

 

Thank you somthing to try!

[James Remo]

If a fixture seems to lag behind it's mates check that the pan / tilt speeds are set to the same (PTSP in the menu) Doesn't explain the home position problem but one we've noticed on our heads quite regularly (but as to who changes the setting we've not found out, probably one of our sub hire clients, the prep techs never used to check this and the effects speed (EFSP) setting)

[IRW]

We had a similar problem with one of our Mac600's a few months ago- turned out to be a broken gear or loose drive band or something along those lines. Might be worth popping the arm cover off just to check!

[mutley]

I know it may seem obvious, but is it displaying any error codes?

"FbEt" perhaps?

If it doesn't know where it is due to the feedback circuit not working, it will not know the current location of the head, so it won't be right again until you reset it. On a reset/switch on, the motors all drive for a few seconds to make sure that all functions are at the full extent one way, and then it calculates it's position from there by counting the number of light pulses it gets from the opto-slot wheel sensor.

 

Even if it isn't giving an error code, check the opto-slot wheel to make sure it's clean and none of the teeth are broken off.

[Kopy]

The tilt sensor is probably dirty - take the arms off and blow it out. While you are there check that none of the teeth on the sensor wheel are broken.

 

A concurrent post has been automatically merged from this point on.

 

Great minds think alike - you must have been typing that at the same time as me!

[Biro]

Are you using a Terminator on the end of it?

[saturnx21]

There will be two sensors on the tilt one will be an optical sensor and the other a magnetic sensor the optical one is there if the head is moved whilst powered up this is so the head always knows where it is and can reposition itself after being moved (ie: someone bangs in to it) the magnetic sensor/switch is to zero the unit at it's start point if the head is not going to it's true start position then it is quite likely to be this magnetic sensor that is not working correctly either muck, sensor fault or broken loom. The optical sensor is easy to check, just manually move the head whilst it is powered (wait until after the unit has finished it's start up procedure) if the head returns to it's position (where it was before you manually moved it) then the optical sensor is working correctly. Testing the magnetic sensor is not so easy, as really you need the unit in bits and be able to disable the pan! this is best left to an experienced engineer.

 

when I say manually I do literally mean grab hold of the head and move it against the motors (you don't need to go mad just move it a few degrees!)

 

HTH

[Matt Cowles]

There will be two sensors on the tilt one will be an optical sensor and the other a magnetic sensor the optical one is there if the head is moved whilst powered up this is so the head always knows where it is and can reposition itself after being moved (ie: someone bangs in to it) the magnetic sensor/switch is to zero the unit at it's start point if the head is not going to it's true start position then it is quite likely to be this magnetic sensor that is not working correctly either muck, sensor fault or broken loom.

 

Not all of what you have said here is true. There is no magnetic sensor for the pan or the tilt in any MAC fixtures. The pan and tilt circuits work with an optical sensor which is how the fixture knows where it is when it is moving around, basically there is a white toothed wheel that passes through the optical sensor when the fixture moves and the fixture counts the teeth as it moves so that it always arrives in the correct position. The magnetic sensor you are referring to is in fact not a sensor and not magnetic, it is in fact a micro switch. The purpose of the micro switch is to tell the fixture where its end stop is, when the fixture is powered up it will tilt to its end stop and hit the micro switch, when the switch is closed the ficture knows to stop moving. If there is a fault with the micro switch circuit you should get a tilt error (TIER) appear on the screen, which is not happening so I do not think that the micro switch is the problem. That brings us back to the optical sensor. If the fixture has a problem with this circuit you will get a feedback error on the tilt (FBET), so again I don't think this is the problem here.

 

My guess would be one of two things, firstly check that there is no dust or dirt in the optical sensor as poeple have already suggested, but I think the more likely fault is with the white toothed wheel I mentioned earlier. Check that all of the teeth are in tact, if one of the teeth has broken the ficture will not be able to position itself correctly, this will not always show up as a FBET because of the position of the broken tooth.

 

I hope that clears things up, as usual if you have any questions feel free to PM me or call our happy service team on (01622)755442

[saturnx21]

Not all of what you have said here is true.

 

If you read my post correctly it says:

the magnetic sensor/switch

I said this as most units use a magnetic sensor and some use a switch, but anyway the OP said that the head of the unit does not sit at it's correct start point after start up. The optic sense only comes in to play to when the head is moved from where it should be so surely it is more likely to be a fault with the switch than the optic sensor or wheel?

[Ben Lawrance]

Matt Cowles

Product Manager - Moving Heads, Controllers & LED

Martin Professional PLC

 

I'm pretty sure he knows what he's on about...............

[law99]

The optic sense only comes in to play to when the head is moved from where it should be so surely it is more likely to be a fault with the switch than the optic sensor or wheel?

 

I'm pretty sure Martin products use the optical wheel at startup, as well as the end stop switch on the units to find 'home'. It appears to do that on our 250units.

 

As stated I'd check all the settings in the unit are exactly the same, for example I've seen this when units are set to the 'speed' setting for pan / tilt and others not.

 

One last thing to check is that when the unit is resetting, the head turns fully and pushes the end stop sensor (a small pressure switch). We have one unit (250 wash) that was not doing that and exhibiting all the same problems as yours (not resetting to 'home' position, in a different position in the programming to the others).

[Matt Cowles]

Matt Cowles

Product Manager - Moving Heads, Controllers & LED

Martin Professional PLC

 

I'm pretty sure he knows what he's on about...............

 

If you'd met me you'd know that is not necessarily true.

 

The optic sense only comes in to play to when the head is moved from where it should be so surely it is more likely to be a fault with the switch than the optic sensor or wheel?

 

No it is not likelyto be the switch, the switch is there to tell the fixture when it has reached its end stop. When the switch is closed that sends a signal to the main PCB that the software then interprets as the fixture reaching its end stop. If there is a problem with the switch or the wireset from the switch to the PCB (the only components in this circuit) then the fixture will diplay a tilt error (TIER). I would still definately check the toothed opto encoder wheel.

 

Also does the fixture reset to its correct home position if there is no DMX going to the fixture? If it does go home then I would suggest that there may be a problem elsewhere, try doing a factory reset and then setting the fixture up again to match the rest of the rig.

[techtech]

Thank you all for your help. I think it is the toothed wheel which I am not touching. Back to the hire company with it. Honestly it has been really helpful using BR. Keep up the good work all and I'll try to help others where I can!!

 

Thanks again peeps.

 

Hurray the Panto and hurray the Christmas shows!!

 

Love and peace

 

TT