Hey guys,
I am a registered sparky and do many inverter installs at the moment.
I have come across something today which has totally puzzled me. I will get to the bottom of it as I refuse to walk away from anything without a solid answer.
But, maybe one of you guys has seen something like this before...?
I installed a modified square wave inverter today at a clients house.
It's a 360W unit and i have installed many of these before with no hassles whatsoever.
Its just a stand-alone unit by the tv with a battery and a multi plug with tv, dstv, etc connected.
Set it all up and turned off the plug supplying the mains to the inverter to test it, and, what usually happens is the slightest of flicker on the screen (usually not even noticeable) and the channel continues as though nothing has happened.
All good.
Well, today when i turned the power off, the tv stayed on, the decoder stayed on, but the signal disappeared!
I thought that maybe i had left something off of the inverter multiplug that was supplying power to the satellite install.
So i checked again, and found nothing the matter.
Turned the plug back on to supply mains power again, and within a few seconds the channel was playing again!
The satellite system has a PVR decoder, and an old dstv box as the Xtra view decoder and this is supplying the bedroom and kitchen tv's. There is also an LNB multi switch unit which supplies 2 inputs and 4 outputs to the 2 decoders.
Well, switched power off again and noted that both the kitchen and bedroom continued to be supplied with a perfect signal and could change channels no worries.
Just the lounge tv supplied by the PVR was affected!
I checked all the satellite cables and redid the connections and still no joy! As soon as inverter kicks in signal disappears from PVR but still perfect on older decoder!!
I had to leave to get to another appointment so I will be returning there tomorrow to fault find further.
My thinking is that the inverter is putting out some sort of electro-magnetic interference which is disrupting the PVR circuitry somehow?!
Although it is not doing any damage to the old dstv decoder at all. This leads me to believe that it cannot be the multi switch unit either.
Very strange indeed!
I have installed loads of these smaller 360W and 600W inverters as stand-alone packages, and have never come across this problem before!
Granted i cant say whether i have installed this package near another PVR decoder, as it has never occurred to me to check, as this would never have entered my head as being a problem before today!
What i will try tomorrow is to move the inverter and battery to the other side of the room to negate electrical interference and then run an extension lead to supply the tv installation to see if this solves the problem.
If it does then i know that i need to install in the adjoining cupboard and screen the sides of the cupboard to prevent this happening.
If it doesn't solve the problem then i would have to say that the PVR 2P decoder (which is not supported by dstv anymore) must be the faulty device, or at least the culprit, as it does work on mains power!
I could no doubt install a pure sine wave inverter but this negates the idea of supplying a cheaper option for my clients.
Anyone else come across this before??
Simon