Hi,

I am doing a spec which will require expanders? It will be grade 2 but i am not sure do i have to fit a psu to comply to the standards? I am sure you have to for grade 3 but no sure for grade 2?

I am also connecting smoke detectors to this system is there anything like breakglasses which i can connect to this sysem?

Any info much appreciated.

mrg

Hi,

I am doing a spec which will require expanders? It will be grade 2 but i am not sure do i have to fit a psu to comply to the standards? I am sure you have to for grade 3 but no sure for grade 2?

I am also connecting smoke detectors to this system is there anything like breakglasses which i can connect to this sysem?

Any info much appreciated.

mrg

system is graded to the grade (or lack off) of the lowest graded item on the system

a normal MCP can be put on a system BUT fire bits on an intruder are nowhere the same thing as a proper fire alarm

What i meant was for every expander do you have to fit a PSU?

Thanks

depends , design based on volts drop, loading (standby & alarm) & size of battery fitted to psu

dont believe its a specific part of the grading as long as your within the limits for the panel

for any system even G1 you need to know what the panel can supply as 'spare' current, the current draw of attached equipment like pits, dualtecs and also the cable distance's for voltage drop issues, you also need to add in the consumption of the expanders.

do all that and then add at least 30% margin to allow for batteries to recharge after a substantial power fail.

for G3 i think you need 'intellegent' psu's i.e. ones monitored by the main panel

regs

alan

thers a new way of calculating max power available but I`m dammed if I can remember it - trip to car later