greenalien Posted July 22, 2006 Posted July 22, 2006 Stairville DMX 200 StrobesThese strobe lights are supplied by Thomann, but there are other similar devices on the market. Good value for money, but there's a safety issue if you just connect them up as shipped. I have e-mailed Thomann with the following :- ------------------------------------------------------------------------------------- Having just taken delivery of 4 of these strobes, may I suggest that the instructions need the following amendment : "These units are shipped with MASTER mode set to ON. MASTER mode MUST be set to OFF before connecting the strobes to a DMX controller or an existing DMX network. Press the MENU button until MAST is showing on the display. Press the ENTER button, then use the DOWN or UP button to select NO. Press ENTER to confirm setting." I believe it is important to provide these additional instructions because otherwise the units will TRANSMIT data on the DMX connection that could cause serious damage to any other DMX devices that are connected at the same time, including unwanted lamp striking and unexpected and rapid Pan and Tilt movements. -------------------------------------------------------------------------------------------- I found out the hard way - I connected up my new strobes to an existing DMX rig, powered it all up, and everything went haywire! Thought I'd post this here to save anyone else having the same problem.
paulears Posted July 23, 2006 Posted July 23, 2006 I thought for a bit before posting this. I think I have firmed my opinion up now. Plgging in a piece of kit that from the perspective of anything else on the chain transmits isn't really a sin. Plenty of budget mirror fixtures automatically start to transmit if their DMX in gets interupted. Some things respond oddly just because there isn't a DMX in. Fair enough, these strobes MAY do odd things, but the chances of you having set overlapping DMX channels is a bit unlikely, and, from the manufacturers perspective, the book does mention the purpose of the switch. You might get the distributor to persuade the manufacturer to reprint, or put in a notice, or even change the process at the factory - but realistically, I can't see they'll be too worried as their response would be - why don't people check before powering up? I've had this happen to me when plugging up a DMX smoke machine. Out of the box, fulid up, plug in DMX, set address, walk away and do next job - only to have it suddenly go to full smoke as soon as it heated up. The book says I have to prod a few buttons - I didn't.
bruce Posted July 23, 2006 Posted July 23, 2006 As Paul says... To me, this is just an operational issue. It's not a safety issue.
greenalien Posted July 23, 2006 Author Posted July 23, 2006 The reason I've posted this as a Safety issue is because these strobes transmit on the DMX line even when the line already has a valid DMX signal on it, unless MASTER mode is disabled. Although the manual does describe how to deselect MASTER mode, it makes no mention of this being the default setting, or of the need to disable the setting before setting up DMX addressing. Why is this a safety issue? Well, if you have fixtures like moving heads that unexpectedly start going through a full range of rapid movement and discharge lamps that attempt to strike, then switch off and then try to strike again, then you are likely to get damaged equipment - and if anyone is working next to a fixture that moves violently and unexpectedly then there is the potential for injury as well.
bruce Posted July 23, 2006 Posted July 23, 2006 Why is this a safety issue? Well, if you have fixtures like moving heads that unexpectedly start going through a full range of rapid movement and discharge lamps that attempt to strike, then switch off and then try to strike again, then you are likely to get damaged equipment I don't deny that this is undesirable, but it's hardly safety-related... ...and if anyone is working next to a fixture that moves violently and unexpectedly then there is the potential for injury as well. If anyone is working next to a fixture which is powered up and connected, they should be aware that it may move. That's why they call them "moving lights" :) . Your risk assessment and working practices should take this into account. I'm not suggesting that the behaviour of these units is acceptable, or otherwise. All I'm suggesting is that this isn't an appropriate instance to play the Health & Safety card... Edit: fixing quotes.
niclights Posted July 23, 2006 Posted July 23, 2006 I think it is a bit of a myth that you could damage equipment by sending random DMX data. The motors and components will be designed to move at that speed and may often do in normal use. If you continually make everything move at max speed in some sort of crazy disco then I'm sure you reduce life, but for a few seconds? As for lamp strikes, although this certainly is undesirable and would reduce lamp life, most (if any?) simply won't be able to re-strike so fast and therefore this is probably not going to happen before you realise the error and that assumes the unlikely coincidence of actually sending the correct data to make this happen.
Nick Evans Posted July 24, 2006 Posted July 24, 2006 Hardly a safety issue. Who is likely to get hurt? As for fixtures damaging other fixtures, not quite as ironic as fixtures damaging themselves (witness a well known manufacturer issuing software upgrade to stop bits of the colour mech trashing other bits. Still, it only took them 2 years).
Recommended Posts
Archived
This topic is now archived and is closed to further replies.