Setting Example - Omron K8AC-H Manual

Using the Power Regulator's Gradient
Settings
The power regulator's gradient settings can be used to prevent
malfunction by setting the operation gate current level. The
relationship between the gradient settings and output current
depends on the power regulator manufacturer and model, so be sure
to check the characteristics of the power regulator being used before
setting.

Setting Example

Initial setting: 7 mA
Output current
100%
Measurement range
0%
4 mA 7 mA
Not detected
When the power regulator's gradient settings are changed, the
operation gate current level is set so that the output current is within
the measurement range. (In the following diagram, 14 mA is set.)
Output current
100%
Measurement range
0%
4 mA
Not detected
Using Halogen or Other Heaters with
Varying Resistance during Phase and
Cyclic Control
When phase control is used with halogen heaters or other pure metal
heaters, the heater resistance fluctuates according to the control
level. As a result, high-precision detection of heater burnout is not
possible. The effect on the heater and setting methods depends on
the heater being used. Therefore, consult with your OMRON
representative before using a heater with varying resistance values.
Halogen Heater Resistance Fluctuation
Example
In the following example, burnout of one element in a six-element
heater can be detected at a control level of 20 mA, but detection is
not possible due to the effect of fluctuating resistance if the control
level is any lower.
Heater resistance
8 Ω
Detectable range
6 Ω
4 Ω
Threshold
2 Ω
0 Ω
4 mA 7 mA
Gradient
setting 100%
Control signal
20 mA
Detected
Gradient
setting 100%
Gradient
setting 50%
Control signal
14 mA 20 mA
Detected
Three elements
burned out
One element
burned out
Normal
(six elements in parallel)
Control signal
20 mA
K8AC-H
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