Omron H7CX- -N Series Page 53 Manual Download

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H7CX-

-N

• H7CX models with a 12 to 24-VDC power supply use a

transformer-free power supply method in which the power supply
terminals are not isolated from the signal input terminals. If a non-
isolating DC power supply is used, unwanted current paths may
occasionally burn or destroy internal components depending on
the wiring. Always check the wiring sufficiently before use.

• An inrush current of approx. 10 A will flow for a short time when the

power supply is turned ON. If the capacity of the power supply is
not sufficient, the Counter may not start. Be sure to use a power
supply with sufficient capacity.

• Maintain voltage fluctuations in the power supply within the

specified operating voltage range.

• When turning the power ON and OFF, input signal reception is

possible, unstable, or impossible as shown in the diagram below.

• Inrush current generated by turning ON or OFF the power supply

may deteriorate contacts on the power supply circuit. Turn ON or
OFF to a device with the rated current of more than 10 A.

• The capacity of the external power supply is 100 mA at 12 V. When

using a 24 VAC/12 to 24 VDC power supply, reduce the load with
the power supply voltage, as shown in the following diagram (DC
power supplies only).

• If the prescale value setting is incorrect, a counting error will occur.

Check that the settings are correct before using this function.

• Make sure that all settings are appropriate for the application.

Unexpected operation resulting in property damage or accidents
may occur if the settings are not appropriate.

• Do not leave the Counter for long periods at a high temperature

with output current in the ON state. Doing so may result in the
premature deterioration of internal components (e.g., electrolytic
capacitors).

• EEPROM is used as backup memory when the power is

interrupted. The write life of the EEPROM is 100,000 writes. The
EEPROM is written at the following times:

• When the power supply is turned OFF
• When switching from Configuration Selection Mode or Function

Setting Mode to Run Mode

• Dispose of the product according to local ordinances as they apply.

• Attach the front panel when using the Counter. The tabs in the

middle of each of four sides secure the front panel to the main
body. To remove the panel, widen the four tabs and pull the panel
toward you.
To mount the panel, fit all four tabs correctly into the grooves on the
main body.

• When conforming to EMC standards, refer to the information

provided in this datasheet for cable selection and other conditions.

• This is a class A product. In residential areas it may cause radio

interference, in which case the user may be required to take
adequate measures to reduce interference.

• H7CX-A

-N: Basic insulation is provided between power supply

and input terminals, between power supply and output terminals,
and between input and output terminals. (However, no insulation is
provided between the power supply and input terminals for the
H7CX-A

D-N.)

• H7CX-R

-N: Basic insulation is provided between power supply

and input terminals and between input and output terminals.

• When double insulation or reinforced insulation is required, apply

double insulation or reinforced insulation as defined in IEC 60664
that is suitable for the maximum operating voltage with clearances
or solid insulation.

• Connect the input and output terminals to devices that do not have

any exposed charged parts.

Precautions for Correct Use

Input

Impossible

200 ms

5 ms

0 to 90 ms

0 to 1 s

Possible

Unstable

Unstable Impossible