Kobold KMT-1, Руководство пользователя, Страница: 30 / 36

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5.1.5. Output mode – switch (relay)
In the field for the “Switch-mode”, one can select “Hysteresis” or “Window”.
The field for “Type” is to determine the switch action of the relay, NO = Normally Open (activate to close), NC
= Normally Close (activate to open).
Under “Measuring range” in the field “From” the low value of the measuring range can be entered and in the
field “To” the high value.
The hysteresis of the set point is entered as a percentage of the
measuring range.
[measuring range] = high measuring value – low measuring value
e.g. hysteresis
set point = 500 Nm3/h and reset point is 450 Nm3/h
Hysteresis = 50 Nm3/h = 0.5 % of measuring range
Hysteresis
t
Nm 3 /h
0
1
0
1
NC (activate to open)
NO (activate to close)
set point 1
Hysteresis
When the measurement value reaches set point 1 , the relay will be
activated. The value at the reset point is the value at set point 1
minus the hysteresis.
e.g. set point 1 = 100 Nm3/h and the hysteresis 5 Nm3/h.
the relay switches at 100 Nm3/h. The reset point is at 96 Nm3/h.
Hysteresis = 5 Nm3/h = 5% of the measuring range
Window
t
Nm 3 /h
0
1
0
1
set point 1
set point 2
NC (activate to open)
NO (activate to close)
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The relay is activated as long as the measuring value is
between the values of set point 1 and set point 2 .
The hysteresis of each set point is fixed at 0.2% of the measur-
ing range.
e.g.: set point 1 = 100 Nm3/h; set point 2 = 80 Nm3/h;
hysteresis of each set point is 1 Nm3/h (0.2% of 500 Nm3/h)
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‚
ƒ
„
80 Nm3/h = set point 2
100 Nm3/h = set point 1
99 Nm3/h = set point 1 - hysteresis
79 Nm3/h = set point 2 - hysteresis