Modbus communication error

[automatikas]

missed the post. It does work fine.

i used for loop as i have 36 devices

Code:

offline_time = 600 --offline detection time in seconds

-- for i = START, STOP, STEP
for i = 1, 36, 1 do
 address = ('13/1/'..i)
 obj = grp.find(address)
 delta = os.time() - obj.updatetime
 address = ('13/0/'..i)
 if (delta > offline_time) then
   grp.update(address, false)
 else
   grp.update(address, true)
 end
end