2.
Pulse Frequency control
The illustration of pulse frequency control as follows. The relay makes
frequency proportion ON/OFF control according to control output volume u.
When ON time is fixed as 0.3 sec, the OFF time is related to the setting of
maximum frequency. For example, the maximum frequency is set as 60 p/min.
When u=100%, the action frequency of relay is 60 p/min. It represents that each
second the device finishes one ON/OFF control. Thus, the OFF time is:
(1 - 0.3) = 0.7sec.. While u=50%, the maximum frequency is set as 30 p/min. It
represents that every two seconds the device finishes one ON/OFF control, and
thus the OFF time is: (2 - 0.3) = 1.7 sec.
ON time 0.3 sec
0
1
Max frequency (u=100%)
ON time 0.3 sec
0
1
50 % Max frequency (u=50%)
ON time 0.3 sec
0
1
Max frequency (u=100%)
ON time 0.3 sec
0
1
50 % Max frequency (u=50%)
3.
Analogout control (0/4~20 mA)
The current output and control output u value are set as corresponding
proportional relationship. The relationship is described as follows: Under
0~20mA mode, the current output = u*20 mA; under 4~20mA mode, the current
output = 4 + u*(20–4)mA. Take “u=50%” for an example, under0~20 mA
mode, the current output is 10 mA; while under 4~20 mA mode, the current
output is 12mA.
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