Omron CRT1 - 10-2008, Руководство по эксплуатации

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Functions Unique to Bit Slave Units Section 11-6
Note If the power supply is not turned OFF after making an adjustment, it
is not necessary to wait 30 minutes before continuing testing.
11-6 Functions Unique to Bit Slave Units
11-6-1 Power Short-circuit Detection (Input)
Description
This function monitors the sensor power supply current. If the current is
80 mA or higher per input contact, a power short-circuit is detected.
The I/O power for the Slave Unit turns OFF if a short-circuit is detected for
even just one of the contacts being used.
The Slave Unit SHT0 indicator can be used to check whether a power short-
circuit has been detected. When a power short-circuit is detected, a flag in a
status area in the Slave Unit turns ON to notify the Master Unit. The notifica-
tion details can be read using the CX-Integrator or using explicit messages.
When the cause of the short-circuit is removed, the Slave Unit is automatically
reset, and the power output to the connector that had the short-circuit is
turned ON again.
Note Use a power supply rated 100 W or higher as the communications power sup-
ply. A short-circuit is detected if a current of 80 mA or more flows for two
inputs in the Unit's sensor power output. The communications power supply
may be temporarily cut if a short-circuit occurs. The Slave Unit is automati-
cally restored after the cause of the short-circuit has been removed but exter-
nal circuits must also be created to ensure safe system operation while the
power is disconnected. Use the following formulas as a guide for calculating
the sensor current consumption.
• Total network current = Total Unit current consu total sensor cur-
rent consumption
• Communications power capacity used
≥
{total network c (short-
circuit detection current = 80 mA)}
×
(CompoNet network voltage)
Checking Using the CX-Integrator
1,2,3... 1. Turn ON the power supply to the CompoNet Slave Unit.
CRT2-TS04P
Six-dial
resistance box
Input A
Input B
Input b
Short-circuit
Sensor
Short-circuits in the
sensor power supply can
be detected.