Example : DO11+DO12 alarm output
Alarm occurs with current I1 goes over 1 A for a duration of more than 15 seconds.
1. Set the mode of DO11 as mode 1 (alarm output).
2. Set alarm time to 15 seconds, 1 digit represents 300 ms:
• The value is: 15 ÷ 0.3 ＝ 50.
3. Alarm output item is I1, and value must be set to 7.
4. I1 must be higher than 1A, so the alarm function must be set to 1 (High alarm = 1).
5. Set alarm limit to 1A (use direct primary values).
Energy pulse output
The two digital outputs can be used as energy pulse outputs. The output energy can be selected among all kinds of active and
reactive energy terms. Pulse rate and pulse width can be set to meet the requirements.
Pulse constant is the amount of kWh for each pulse.
Pulse width is the time that a pulse lasts.
When the accumulated energy reaches the pulse rate value, there will be a pulse on the digital output.
Related parameters:
Pulse energy output ranges from 0 to 4 corresponding to none, Ep_imp, Ep_exp, Eq_imp, Eq_exp.
Pulse rate ranges from 1 to 6000 (integer) with a unit of 0.1kWh (kVArh), apparently that is the resolving power of energy output.
Pulse width ranges from 1 to 50 (integer) with a unit of 20ms. The narrowest interval between two pulses is 20ms.
In practice the pulse width and the pulse ratio are selected according to system power. The relation of the two parameters should
satisfy the following expression:
is the maximum power or reactive power.
The unit is kW or kVAr. Recommended pulse rate is 3 to 5 times the right side value of the above expression.
DESIGNER'S HANDBOOK 4189320063D EN Page 11 of 23
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