Emergency Light Test Switch.

mapj1:

Normally the self test is not a full 3 hour run down, rather the NiMH runs it down for about 30 mins, and verifies that the cell voltage drop is 'on track' not to fail in the declared time. The larger lead acid units are tested by verifying internal impedance from a very short high current discharge - a higher than expected voltage droop indicates loss of useful plate area, and reduced capacity, While both methods are a bit approxmate, usually it is pretty good, within about 10% of a proper capacity test.

It is more important in such cases to re-fit the right sort of replacement battery, as a change of chemistry, or the use of a gel lead acid instead of liquid filled a glass fibre mat can confuse the self test, either into warning when it should not, or worse, not warning when it should.


Mike

Far too clever for a simple soul like me. :( 


I have just read the instructions and the emergency lights only do the full test, that say it will take three hours, at a random time in the 24 hours after commissioning. After that it does its short checks weekly and requires a button on the light to be pressed to instigate a full test at a random time in the following 24 hours. 


The Emergency Exit signs are the same make and have a similar commission and short test process but also say they will do the full test every 12 months. They do not have a button to press to perform the full test at another time. 


The emergency light test switch, key operated :) ,  will have to be used to test both types as some of the emergency lights are mounted over four metres from the floor. 


Am I alone in thinking that while trying to make things simpler they become more complicated?

mapj1:

Normally the self test is not a full 3 hour run down, rather the NiMH runs it down for about 30 mins, and verifies that the cell voltage drop is 'on track' not to fail in the declared time. The larger lead acid units are tested by verifying internal impedance from a very short high current discharge - a higher than expected voltage droop indicates loss of useful plate area, and reduced capacity, While both methods are a bit approxmate, usually it is pretty good, within about 10% of a proper capacity test.

It is more important in such cases to re-fit the right sort of replacement battery, as a change of chemistry, or the use of a gel lead acid instead of liquid filled a glass fibre mat can confuse the self test, either into warning when it should not, or worse, not warning when it should.


Mike

Far too clever for a simple soul like me. :( 


I have just read the instructions and the emergency lights only do the full test, that say it will take three hours, at a random time in the 24 hours after commissioning. After that it does its short checks weekly and requires a button on the light to be pressed to instigate a full test at a random time in the following 24 hours. 


The Emergency Exit signs are the same make and have a similar commission and short test process but also say they will do the full test every 12 months. They do not have a button to press to perform the full test at another time. 


The emergency light test switch, key operated :) ,  will have to be used to test both types as some of the emergency lights are mounted over four metres from the floor. 


Am I alone in thinking that while trying to make things simpler they become more complicated?