Omron G3ZA - MANUAL 2 User Manual page 61

Detecting Heater Overcurrent (4-channel Models Only)
Note
Note
1,2,3...
Precautions
44
tion, heater overcurrent detection, and SSR short-circuit detection func-
tions.
Variable type Parameter name
81/C1 Channel 1 to 4 heater overcur-
rent detection value
CT 1 to 4 heater overcurrent
detection value (
83/C3 Hysteresis
If set to 50 A (or 165 A in the
detected. If set to 0, detection is forced. Use these settings to confirm opera-
tion during installation.
Setting Ranges Supported in the
The current range and units are determined by the Current Monitor Selector
setting.
Variable type Parameter name
83/C3 Current Monitor Selector
Detection values of 0 to 165 (A or %) max. can be detected, but set the detec-
tion value appropriate for the current range. If the detection value is set above
the current range, errors will not be detected. Refer to 4-3 Selecting the CT (4-
channel Models Only)
V2
Example: Setting the CT1 Heater Overcurrent Detection Value to 20 A
1. Set the CT1 heater overcurrent detection value to 20 with a Variable Area
Write command.
2. The current is detected in CT1, and heater overcurrent is detected with the
timing shown in the diagram on the preceding page.
3. Once the CT1 heater overcurrent detection value is written, the setting is
saved, and will also be effective the next time that the power is turned ON.
• The actual current flowing in the heater may not be the same as the
heater's rated current. Check the heater current under actual conditions
using the CT1 to CT4 Heater ON currents.
• Detection will be unstable if there is only a small difference between the
normal current and the overcurrent setting. To achieve stable detection,
set the parameters as follows:
• For a Current Monitor Selector setting of 0 (0 to 50 A):
Heaters of less than 10 A: (Normal current - Overcurrent setting) ≥ 2 A
Heaters of 10 A or more: (Normal current - Overcurrent setting) ≥ 3 A
• For a Current Monitor Selector setting of 1 (0 to 150 A):
Heaters of less than 10 A: (Normal current - Overcurrent setting) ≥ 6 A
Setting range
0 to 50 A (See note.) 50 (Disabled)
0 to 165 A, or %
(See note.)
V2
)
1 to 10 A, or %
V2
models), heater overcurrent will not be
V2
Models (0 to 165 A, or %)
Setting Current range
0 0 to 55
1 0 to 165
2 0 to 110
on page 33 for details on detection values.
Detection will not be stable if the difference is less
than 2 A.
Detection will not be stable if the difference is less
than 3 A.
Detection will not be stable if the difference is less
than 6 A.
Section 4-6
Default
165 (Dis-
abled)
1
Units
A
A
%