990XCP98000 SQUARE D, 990XCP98000 Datasheet - Page 41

• Manufacturer Part Number: 990XCP98000
• Description: QUANTUM CPU BATTERY FOR S
• Manufacturer: SQUARE D

Specifications of 990XCP98000

• Rohs Compliant: YES
• Battery Capacity: 1800mAh
• Battery Technology: Lithium
• Battery Voltage: 3V
• Battery Terminals: Connector
• Weight: 0.12lb

Presentation
(continued)
Modicon
automation platform
Safety I/O modules
As can be seen on the diagram above, apart from the input terminal block screw,
and the connection to the backplane, the module is internally fully redundant.
The input is connected to two different measuring devices, each controlled by
a microprocessor.
The + 24 V sensor supply voltage is also supplied to each of the two measurement
channels, where its validity is tested. Each microprocessor stores data, then checks
that the measuring systems have worked correctly before sending them to the PLC
processor. Thus, each microprocessor:
b
b
b
the data frame is 160 bits (1). The ratio of these CRC and frame lengths is such that
the risk of non-detection of a transmission error on the assembly is minimized.
For each input, both measurement channels must of course send the same data to
the CPU. This is checked by the “vote” function
degradation of the data between the microprocessor stage and the connection to
the backplane.
(1) 140 SDI 953 00S: 64 bits. 140 SDO 953 00S: 64 read bits, 32 write bits.
The digital input monitors the sensor power supply on the process side.
The external wiring is checked by leakage current measurement.
The minimum current is 1 mA. If it does not reach this value, this is deemed to mean
an external failure due to a break in the circuit.
If a sensor with volt-free contacts is used, a 15 kΩ pull-up resistor is required at the
+24 V to avoid detection of the circuit break.
Diagnostics of the safety discrete input module
140 SDI 953 00S (continued)
Internal diagnostics
Input channel error detection
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Time-based data
Identification of the module and its address
CRC on 32 bits for transmission with maximum reliability. The maximum length of
140 SAI 940 00S: 160 bits.
Imposes levels 0 and 1 on its measuring system, and checks that the values read
are indeed consistent with these levels.
Checks the presence of the + 24 V voltage, needed to validate the measurement.
Spies on the other microprocessor, checks that it has indeed complied with the
diagnostic and measurement protocol. Both microprocessors exchange data,
and compare their measurement results. Then each one defines its response to
the CPU by preparing a secure response frame containing the following data:
The supply voltage from the backplane is also monitored. The module places
itself in a safe fallback position in the event of undervoltage or overvoltage of this
supply voltage.
®
Quantum
™
5
that helps to eliminate any risk of
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