hi

i have installed about 7 scantronic 9752 with expanders in 7 diferent locations

all of them came randomly with the fault kp01 missing exp01 missing

the only way to reseted was to disconnect the battery and power

we changed the panels with replacemnts send by scantronic but same fauls came up after a while

we have installed many other scantronic panels but this 7 cose us such a greef

scantronic technicles said that are site conditions and install spike suppresors witch we did but with no luck

das anyone know what can be the problem?

thank you andy

how are they cabled? What is the distance on the data lines ie to expanders / keypads. Are they locally powered or from the panel?

What was the day mode current if all powered from the panel?

thank you for the quick replay

they are cabled star and the distance is unde 50m

we have changed the cable with shilded alarm cable as the technicle recomanded

but the same problem

the power is from the panel but we used diferent power for pirs from aux

the most pirs we have are 7 on one system

regardes andy

50m might be too much without local power. What is the power demand at the expander etc?

we did separate power for pirs from aux output and doubled the cores for data

scantronic recon that 50m is ok as long the data is doubled

the amp is not exceding 300mA

ok

'doubled the cores for data'

do you mean the power or the data here?

used 12 core shilded cable 8 core for data and 4 core power for pirs

Edited August 31, 201114 yr by andyprutica

You shouldn't be doubling up the data. You will be causing all sorts of reflection issues with a doubled data line.

thanks i will do the data on the last install

and well wait

thanks again

double the power mind use all cores for power, but only a single pair for data