Epiphan’s VGA Splitter eliminates VGA ground loop Problems

Ground loop in an electrical system refers to an unwanted current. Ground loop connection exists when several devices in an electrical system are connected through different ways to a common ground. As currents flow through these paths, they develop voltages which can cause damage and noise. Ground loops created by improperly installed or improperly designed equipment are a main cause of noise and interference in audio and video systems. They are able create an electric shock hazard since ostensibly “grounded” parts of the equipment, which are often accessible to users, are not at ground potential.

VGA Splitter GLI™ from Epiphan featuring built-in ground loop isolation helps our customers prevent ground loops and achieve high quality of the VGA signal. As is known, in video, ground loops are seen as hum bars scrolling vertically up the screen. It is important to get rid of them when installing and setting video equipment. Read further to know how VGA Splitter solved this problem as one of our customers in the UK reported.

“We were installing video and audio equipment in a hall where our events take place throughout the year. We use projector and monitors to show presentations, visuals and images to the audience. From the very beginning we ran into a VGA Ground Loop problem. As you know, this kind of problems cannot be predicted beforehand. Only after you have installed the system it can be determined if a problem will exist. Ground loop is a common problem when multiple audio-visual system components are connected together.

VGA Splitter diagram

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After turning on the projector we noticed hum bars. I am sure that our system was installed properly. The first recommendation we’ve got was to remove the mains earth connections to the projector and monitor. However it is impossible to remove these connections for safety reasons. In the UK the nominal mains voltage is 240 Volts and mains wiring is in the form of a loop (ring main). We also have an audio induction loop system – the loop of cable around the hall which generates a magnetic field picked up by a hearing aid. So, the induction loop was inducing currents in the ring main earth. We have now installed the VGA Splitter GLI and started to use the system. The ground loop problem is solved. The pictures are accurately displayed on a projector and a monitor.”