Burkert Type 8681 - Manual (Page 62)

62
120 V AC - Design
design aid 13.3.
power consumption of the electronics:
P
El
= 1.2 VA or I
El
= 10 mA at 120 VA
power consumption of a valve during activation (200 ms):
P
Valve-ON
= 1.7 VA or I
Valve-ON
= 14 mA at 120 VA
power consumption of a valve after reduction:
P
Valve
= 1.4 VA or I
Valve
= 12 mA at 120 VA
power consumption of an optical position report:
P
LED
= 1.6 VA or I
LED
= 13 mA at 120 VA
Also, if several control head valves were to be opened simultaneously, the switch signal will be sent stag-
gered to the valves. Only
one valve 1.7 VA will ever be recorded.
Calculation examples:
example 1:
3 valves are activated simultaneously, one position is reported (state for 200 ms):
P
Total
= P
El
+ 1 x P
Valve-ON
+ 2 x P
Valve
+ 1 x P
LED
7.3 VA = 1.2 VA + 1 x 1.7 VA + 2 x 1.4 VA + 1 x 1.6 VA
or
I
Total
= I
El
+ 1 x I
Valve-ON
+ 2 x I
Valve
+ 1 x I
LED
61 mA = 10 mA + 1 x 14 mA + 2 x 12 mA + 1 x 13 mA
example 2:
3 valves have been activated simultaneously, one position is reported (persistent state):
P
Total
= P
El
+ 3 x P
Valve
+ 1 x P
LED
7.0 VA = 1.2 VA + 3 x 1.4 VA + 1 x 1.6 VA
or
I
Total
= I
El
+ 3 x I
Valve
+ 1 x I
LED
59 mA = 10 mA + 3 x 12 mA + 1 x 13 mA
When using an external initiator, its power requirement should be added.
english
Control Head Type 8681