dms hud hang

zaiful

hi,i got one NI300 and connected to 2 dms hub box and 3 more slave NI.The problem is everytime there is a thunderstorm,the dms hub box will hang.Got 2 MVP and will work well.it only the hud.The NI3000 i did some modification on the power supply.i did some testing last time,when i connect neutral cable to NI3000 and reboot by turn off the power source and turn it on again then my hub box will hang.To make it work i got to reboot the hub box.Now i did not connect the neutral cable it working well even u turn off then turn again.It will reboot then all DMS keypad will work.i connected ground cable to NI body and DMS hud box.My question is:
1) How NI3000 can work with out neutral?
2)Why DMS hub box hang when threre is thunderstrom only?
this system got UPS and power surge protection.

regard,
zaiful

DHawthorne

When you say you removed the neutral, I assume you meant ground? Because if you are really removing the neutral, then it must be shunting the neutral to ground or nothing would work. I can't imagine, if all are powered from the same place, that there would be some sort of ground fault unless the wiring was just plain wrong. That's got to be the first thing you check, the electrical wiring. A UPS won't help with a ground loop ... but you could eliminate that possibility by plugging the hub and the controller in the same UPS ... unless of course, the UPS is bad.

If all is well there, what I would do next is put some manner of AC switch on the DMS hub (like a Niles AC3, or one of the AMX power manager boxes). I would tie that to a relay output on the NI, and only turn it on say, 30 seconds or a minute, after the NI starts up. That way any time the system resets, the hub doesn't activate until the rest of the system has settled down ... and it also gives you a way to reset it from a control panel or remotely.