Burkert 8681 - Design Aid

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AS Interface - Design
NOTE!
If all 3 solenoid valves are simultaneously controlled via the AS interface, the electronics will activate the
valvessequentiallywitha200mstimedelaytoprotectthebusfromoverloads.
External power supply for solenoid valves:
External power supply: 19.2 V DC to 31.6 V DC
The power supply unit must include a secure disconnect in
accordance with IEC 60364-4-41. It must conform to the SELV
standard. The ground potential must not have a ground connection.
Power consumption from external
power supply for outputs
(solenoidvalves)-withoutintegrated
currentlimiting:      <110mAat24VDC(for200msafterswitchingonofthe3.
rd
valve)
Power consumption from AS-i
forinputsanddisplay:     <150mA(incl.externalinitiator,feedbackandfaultdisplay)
Integrated short-circuit protection
Pleaseconsiderthefollowinginformationtopowerrequirementandtothemaximumexpansion
stage of the AS interface network in chapter “12.3Numberofconnectablecontrolheads” and in the
ASinterfacespecications,whereapplicable.
12.6 Design aid
Design aid for supply of the valves via the AS-i bus
Power consumption of the electronics:
P
El
=1.0W or I
El
=33mA at 30.5 V
Power consumption of a valve during activation (200 ms):
P
Valve-ON
=0.9W or
I
Valve-ON
=30mA at 30.5 V
Power consumption of a valve after reduction:
P
Valve
=0.6W or I
Valve
=20mA at 30.5 V
Power consumption of an optical position report:
P
LED
=1.0W or I
LED
=33mA at 30.5 V
For the design of the maximum line lengths observe chapter
“12.4Maximumlengthofthebusline”.
Even if several control head valves are switched simultaneously via the bus, the switching signal is
passed on to the valves in staggered order, i.e. only one valve is ever taken up 0.9 W.
english
Control Head Type 8681