Key switch for emergency lights

[bhamoggy]

Hi, I’m a bit new to this and I understand how to wire thru a grid key switch for emergency lighting but could someone please explain or show a small drawing how to wire with a key switch so when the key switch is toggled, the lights stay in and only turns off the emergency lights please

 

[MJPD29]

Just break the permanent or emergency feed through the key switch. The switch feed to the rest of the lights should be totally separate.

 

[cliffed]

Just break the permanent or emergency feed through the key switch. The switch feed to the rest of the lights should be totally separate.

Anyone ever seen this done properly.. emg lights only controlled by key switch & not looped of in circuit with other ordinary lights

 

[Mikegh]

The way I seen them done is CTU and multipole n/c contactor in the DB

Each lighting MCB you take a feed through a pole for emergencies

Ctu breaks the poles

 

[Petej999]

Anyone ever seen this done properly.. emg lights only controlled by key switch & not looped of in circuit with other ordinary lights

depends if the EM lights are Maintained or Non Maintained key switch is used for testing purposes..

 

[pirate]

Interesting...
I am no expert on this, but in a recent installation of maintained units, a separate permanent live was installed, without key-switches. Thus, when doing monthly testing we just trip the breaker for the lights and check that the ones with emergency modules stay lit...which they do. We don't check for them staying on for 3 hours, but an hour is fine, as the building is small and can be evacuated in under 2 minutes via 3 exits. Probably not "best practice" but for a small building it works fine.

 

[Mikegh]

Interesting...
I am no expert on this, but in a recent installation of maintained units, a separate permanent live was installed, without key-switches. Thus, when doing monthly testing we just trip the breaker for the lights and check that the ones with emergency modules stay lit...which they do. We don't check for them staying on for 3 hours, but an hour is fine, as the building is small and can be evacuated in under 2 minutes via 3 exits. Probably not "best practice" but for a small building it works fine.

I don't get that?

 

[pirate]

Not sure what you don't get, but I will try to explain if you can elucidate. Thanks.

 

[bhamoggy]

So this is how I drew it up.

 

[Mikegh]

Not sure what you don't get, but I will try to explain if you can elucidate. Thanks.

You mean 2 feeds from the MCB

One for maintained permanent L,
one for general+ maintained s/l

 

[pirate]

Yes, that's pretty much it. Basically, a P/L which keeps the battery charged. However, should the RCBO trip, the emergency option is triggered, and the luminaire stays lit, on battery power. They have an LED on the frame which shows green when all is well and the battery is charging, and red when in emergency mode. Thus, when the luminaire is switched off, at the switch, the battery is still being kept on charge. Tripping the RCBO simulates a loss of power. That is how it is tested, instead of having a key switch in the circuit.

 

[bhamoggy]

So the drawing is correct for both outcomes?

 

[westward10]

The top drawing is preferred as the test facility only isolates the permanent supply, the bottom drawing will also isolate the general lighting.

 

[Mikegh]

The top drawing is preferred as the test facility only isolates the permanent supply, the bottom drawing will also isolate the general lighting.

Is it the same lamp powered by the switched live as the battery

You turn off the switched live ,the lamp goes out and then the key switch brings it back on to prove the backup system ?

 

[Mikegh]

Led maintained bulkhead

What 50,000 hrs life ,low.wattage

Is there any need to be messing with switched lives ?

Keyswitch or rcbo as above and leave it on 24/7 I dunno ?

 

[westward10]

Is it the same lamp powered by the switched live as the battery

You turn off the switched live ,the lamp goes out and then the key switch brings it back on to prove the backup system ?

A maintained emergency light can act in the same way as a normal general light the only difference being the separate permanent supply controlled by the test facility. Aside from that it will switch on and off like any normal light. A maintained fitting will generally have four terminals L1, L2, N and earth although manufacturers may identify the terminals different for L1 and L2.

 

[Mikegh]

A maintained emergency light can act in the same way as a normal general light the only difference being the separate permanent supply controlled by the test facility. Aside from that it will switch on and off like any normal light. A maintained fitting will generally have four terminals L1, L2, N and earth although manufacturers may identify the terminals different for L1 and L2.

Ya I'm familiar with that

What about the led why bother with on/off

 

[westward10]

Ya I'm familiar with that

What about the led why bother with on/off

I'm not sure what you mean.

 

[Mikegh]

I'm not sure what you mean.

Why bother using it as a general light with backup

With LEDs characteristics long life and low power

I would have thought just keyswitch to L1+L2 and permanently maintained

 

[Mikegh]

Can happen sometimes in an emergency that the general lighting isn't on

Makes sense then to leave the led permanently maintained