35
For more information, tips and advice visit www.tvision.technology
Fault Finding
Every TVision camera is built to the highest standards and fully
tested prior to packing. If you experience an problems you need to
investigate your cabling, connections, power supply and monitor.
No Picture From The HD-TVI
There are a number of potential problems that could cause this.
1. Power Supply
The camera can not function without the correct power supply.
A.
Test that the camera has the correct voltage supplying it,
you must do this with the camera connected so that there
is load on the PSU. A 12V DC camera should have at least
10.5V DC connected to it. 24V AC cameras should have at
least 21.5V AC connected to them.
B.
For 12V DC cameras only ever use regulated power supplies so
that you can be sure that the camera is always receiving the
correct voltage.
See online
Tip 259
for the ‘
Dos And Don’ts Of Power Supplies
’
at
www.tvision.technology
.
Tip
2. Cabling
Check there is a picture coming out of the CVBS test output at
the camera. If there is a picture here but not at the DVR it could
be one of the following:
A.
Video loss in composite cable as the run is too long. Usually
you would get a picture up to around 500m with HD-TVI.
B.
Check the quality of the cable used. For best results,
especially with HD-TVI, use a cable with a solid copper core
such as our
antihum branded cable
on
page 40
. Cable with
a solid copper core suffers far less signal loss than cheaper,
inferior cable which only has a copper coated core.
C.
Ensure that the BNC - BNC lead that you connect between
the camera and monitor has no shorts or open circuits. If
you are making your own lead, don’t forget the lead
must have two wires connected to complete the circuit,
Video and Ground.
D.
Ensure all connections to both the camera and DVR are firm
and secure.
Continued on the next page
