FAQ: Battery Backup for EEPROM - OMRON PLC

Question

Is a battery for EEPROM memory backup required when using an EEPROM Memory Cassette with C200HS or C200HX/HG/HE Programmable Controllers?

Answer

 No, the EEPROM Memory Cassette does not require a battery.

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Question

Can a single sensor output be connected to multiple Programmable Controllers Input Units in parallel?

Answer

 The conditions for setting up this type of connection are as follows:

1.The sum of the total input currents of the Input Units must be below the maximum switching capacity of the transistor in the sensor output.

2.The leakage current from the transistor in sensors output may prevent the inputs to the Input Units from turning OFF. You must be sure that the inputs will turn OFF when sensors output turns OFF.
As a condition for this, the input impedance of the Input Unit and the leakage current can be used to calculate the voltage when the sensor output is OFF. You must be sure that this voltage is less than the OFF voltage of the Input Unit.

3.Sensors signal must be long enough to be detected by the Input Units. The ON/OFF signal from Sensors must be longer than the Programmable Controllers' scan time.

The following formula must be satisfied by the above conditions.

Sum of all leakage currents < Maximum switching capacity of transistor in sensors output

The leakage currents of the pulse output for the transistor in the sensor pulse output when it is turned OFF will not cause the Programmable Controllers input circuit to turn OFF (i.e., satisfies the following condition).
Leakage current of output transistor when OFF x Input impedance of input circuit on Programmable Controllers < Voltage at which Programmable Controllers input turns OFF

The Programmable Controllers must be able to detect the sensor’s ON/OFF signal.
Shorter of ON or OFF signal for sensor/pulse output > Length of one Programmable Controllers scan

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Question

Can a single-phase motor be controlled by a 3G3EV Inverter with a single-phase 100-V input?

Answer

 No, a single-phase motor cannot be used. Doing so will cause a failure.

The Inverter creates a virtual alternating current with high-speed switching.

If the Inverter is connected to a single-phase capacitor-start induction motor, the capacitor will overheat and burn due to repetitive charging and discharging, so do not connect to this kind of motor.

In addition, if the Inverter is connected to a split-phase-start induction motor or repulsion-start induction motor, the motor's internal centrifugal switch will not operate, and the starting coil may overheat, so do not connect these kinds of motors. Use a three-phase motor.