FireNet Community
FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: David Rooney on January 27, 2009, 04:01:37 PM
-
We have a panel switching 230v across the auxillary fire relay N/C feeding and controlling 230v door magnets.
The aux relay attached to the main pcb is actually rated to switch 230v ac 10amps so its not the case that things may blow up, but I've always thought it wrong/bad practice to switch 230v within a fire panel.
Is it just "bad practice" or is it really something that just shouldn't happen??
-
Dave ,
The segregation factor springs to mind , and worse case if the panel was on 1 phase and the doors on another you have 415v potential .
Anyone doing this should have their arm connected to the volt free , as its ye-ha mentality.
Just because the manufacturer fitted a readily avaliable component on the system , does not mean its meant to be used in that way, which was probably covered in the manual. :P
-
We have a panel switching 230v across the auxillary fire relay N/C feeding and controlling 230v door magnets.
The aux relay attached to the main pcb is actually rated to switch 230v ac 10amps so its not the case that things may blow up, but I've always thought it wrong/bad practice to switch 230v within a fire panel.
Is it just "bad practice" or is it really something that just shouldn't happen??
Both Dave
-
Why not mount 24v relay in a box beside the panel to switch the doors, not good to have 240v other than the feed within the panel and as someone said it could 415v depending on phases used.
-
I'd go for bad practice Dave as the only mains I like inside the panel is the one in the terminal block going to the transformer.
A short on this across the board is potentially dangerous to you,never mind blowing the bejeezus out of the panel.
-
errr yes and thanks to all the above.
We would normally mount a separate relay outside the panel with 24volt coil.... the segregation bit did spring to my mind but I was taken aback with this internal pcb mounted relay being clearly marked up and rated for 230v.... which seems a little strange if it is "not allowed".
I'll stick to the separate relay methinks.....
-
errr yes and thanks to all the above.
We would normally mount a separate relay outside the panel with 24volt coil.... the segregation bit did spring to my mind but I was taken aback with this internal pcb mounted relay being clearly marked up and rated for 230v.... which seems a little strange if it is "not allowed".
I'll stick to the separate relay methinks.....
That's the best practice in my opinion :)