Technical Data  Electrical controllers  Shock Relay

Notes when utilizing

1. If using the Shock Relay with human transportation or lifting devices, take the necessary precautions with equipment to avoid serious injury or death from falling objects.

2. CT (current transformer)

The CT is essential for current detection (150 Series only )

For more information about the appropriate CT, refer to the page of each series.

3. Model selection for special capacity and/or motor voltage

Normally a Shock Relay can be selected by motor capacity, but when the motor capacity and/or motor voltage is special (a standard Shock Relay can be used up to a maximum of 600V), select a Shock Relay based on the motor rated current value (set current range).

4. Operating power supply voltage

The operating power supply voltage described in the chart is the standard. For operating power supply voltages other than the standard, the 150 Series is available for special operating power supply voltage as a special MTO product.

5. Output relay operation

The output relay operation consists of two modes: the activation type and the reverting type when overcurrent is detected.

In the event of a power outage, make sure to switch off the machine as the sudden activation of the output relay may cause an accident or equipment damage.

1)Activation when overcurrent is detected

The output relay is activated (contact inverts) only when overcurrent is detected.

Corresponding models

ED Series , SB Series (auto reset ), 150 Series

2)Reverting when overcurrent is detected

When the power source for the Shock Relay is ON, the output relay is activated (contact inverts). The output relay, which was activated when overcurrent was detected returns to its original state.

Corresponding models

SB Series (self-holding )

6. Self-holding and automatic reset

The methods used for output relay resetting are self-holding and automatic reset.

1)Self-holding

Even after overcurrent has stopped, the self-holding mode continues to function. In order to return it to normal operation, push the RESET button or cut the operation power supply.

Corresponding models

150 Series

2)Auto reset type

The output relay automatically resets after overcurrent is gone.

3)Self-holding /Auto reset type

It is possible to switch between these two modes.

Corresponding models

ED Series , SB Series

7. Inverter drive applicability

  • 1)Detection accuracy decreases but generally if it is within the 30 to 60 Hz range, it can be used.
  • 2)Even within the 30 to 60 Hz range, when the inverter accelerates and decelerates, and the current increases or decreases, the Shock Relay can sometimes cause an unnecessary trip.
    Slowly accelerate and decelerate or set it so that there is some leeway in load current within the allowable range.
  • 3)Connect the CT to the secondary side of the inverter, but make sure to connect the Shock Relay operation power source to a commercial power source (never connect it to the secondary side of the inverter).

8. Notes

When the inertia of the equipment/machine is large or the speed reduction ratio is large, the Shock Relay may sometimes not work. Conduct a trial test first before putting it into regular use.

The default knob settings for start time/shock time is "min", while current is "max".