Eaton easy800, Руководство пользователя, Страница: 324 / 394

9 Inside 800
9.4 Allowing for the special features of function blocks
320
Control Relay easy800 11/11 MN04902001Z-EN www.eaton.com
Example: Do not wire backwards
The following circuit diagram shows an example of why you should not wire
backwards. In the third rung, the easy800 device finds a connection to the
second rung in which the first contact field is empty. The output relay is
therefore not switched.
Figure 209:Circuit diagram with five contacts, invalid
Figure 210:Circuit diagram with M 01 marker relay
9.4 Allowing for the special features of function blocks
How the

800 device evaluates the high-speed counters
CF, CH and CI
In order to evaluate the count pulses of up to 5 kHz, the high-speed counter
function blocks operate with an interrupt routine. The length of the circuit
diagram and the associated cycle time has no effect on the counter result.
Operating a DC or FT function block
￫
Use one of the 96 auxiliary relays
M.., if you
have to connect more
than four contacts in series.
I 01----Q 04---- I 03-- o
z --------------- k
h -I 02----I 04----------- Ä Q 02
I 01----Q 04---- I 03----I 05--- Ä M 01
I 02----I 04----M 01----------- Ä Q 02
￫
The following has to be taken into account when operating a
PID controller (DC) or a signal smoothing filter (FT):
The cycle time of the program must be less than the scan time
of these function blocks. If the cycle time is greater than the
scan time, these function blocks cannot supply any constant
results.