What does a flashing power light mean on my alarm?

SD your a prat, go away idiot. Acorn is spot on Janet, Its a well known fault indicator on that panel, Does the same thing on a Honeywell Galaxy,
Do as Acorn has suggests.
Nick

N
January 2012

The flashing light showing on the Veritas panel signifies a faulty battery, replace it.
Don't bother with the silly 'testing' as suggested, replace it. 1x 7Ah 12v rechargeable battery, Screwfix will be cheaper than Maplin.

For heavens sake SD, it's about time you learned about alarm systems, how many more times do you have to be told?

acorn
January 2012

Could be battery, If you switch the power to the unit off, battey should take over, if battery faulty, it will not be able to so outside unit will probabley sound, replace internal battery, after checking internal fuses.

SD
January 2012