5POWER SUPPLY MODULE

POINTS

MELSEC-Q

1 : Overcurrent protection

The overcurrent protection device shuts off the 5 V, 24 VDC circuit and stops the system if the current flowing in the circuit exceeds the specified value. The LED of the power supply module is unlit or lit dimly upon a voltage drop.

If this device is activated, switch the input power supply off and eliminate the cause such as insufficient current capacity or short. Then, a few minutes later, switch it on to restart the system.

The initial start for the system takes place when the current value becomes normal.

2 : Overvoltage protection

The overvoltage protection device shuts off the 5 VDC circuit and stops the system if a voltage of 5.5 VDC is applied to the circuit. When this device is activated, the power supply module LED is switched OFF. If this happens, switch the input power OFF, then a few minutes later ON. This causes the initial start for the system to take place. The power supply module must be changed if the system is not booted and the LED remains OFF.

3 : Allowable momentary power failure period

(1)For AC input power supply

y An instantaneous power failure lasting less than 20ms will cause AC down to be detected, but operation will continue.

y An instantaneous power failure lasting more than 20ms may cause the operation to continue or initial start to take place depending on the power supply load.

Furthermore, by using the same AC power supply for the AC input module and the power supply module, it is possible to prevent the sensor, to which the AC input module is connected, from turning OFF when it is ON when the power is turned OFF.

However, if only the AC input module is connected to the AC line, which is connected to the power suppludetection of the AC down for the power supply module may be delayed by the capacitor in the AC input module. Thus, connect a load of approx. 30mA per QX10 unit to the AC line.

(2)For DC input power supply

y An instantaneous power failure lasting less than 10ms (*4) will cause 24VDC down to be detected, but operation will continue.

y An instantaneous power failure lasting more than 10ms (*4) may cause the operation to continue or initial start to take place depending on the

power supply load.

(4: This is for a 24VDC input. This is 10ms or less for 24VDC or less.)

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