Power cut problem

[Guest HAMISHXX3]

My wired //.National Installer.// system (over 15 years old but new to me) is sounding externally when power is resumed after a power cut.

During the power cut the only sounder working is the internal one.

After power is resumed the control panel indicator lights show that one of the PIRDs has been triggered although this is not the case.

Any help would be much appreciated.

[Service Engineer]

It does sound as though the control panel battery may need replacing, perhaps the battery voltage is dropping too much when a power cut occurs.

Is there a make and model number on the control panel..?

[Guest HAMISHXX3]

Thank you far taking the time to reply.

This appears to be a hybrid system composed of three units:

Unit one is a plasic box with 6 vertical arranged leds, one for each of the installed detectors. bar the exit, together with a reset button. The key operated on/off lock is in this unit and requires an 180 degree turn through the vertical to operate. This leads to:

Unit two is approx.28cm.square and originally carried a Lander Alarms logo but an //.National Installer.// label has since been added. It has 5 horizontally arranged leds. the first is supply; second is final exit door; third is marked 1 and is the master for the previous unit of 6 detectors, fourth is marked 2 and had a tag of 24 hours and the final one is STOP.

The 3rd unit is 30cm square with no marking apart from an //.National Installer.// label.

I understand from the previous owner that the system was monitored at one time although this has been allowed to lapse.

I did attempt, with the power supply disconnected, to open unit two to check for a battery but this has an anti tamper device fitted so I quickly closed up without seeing inside!

Three more questions please:

Can I suspend the system whilst I check the battery?

Will the alarm boxes also have backup batteries?

What will the STOP led be meant to indicate on the 2nd unit? Not sure I have ever seen it lit.