Description
Honeywell 900-A01-0202
- Technical Specifications
- Channel count: 8 analog input channels
- Supported signal: 4–20 mA DC current loop
- Resolution: 12-bit ADC
- Backplane interface: HC900 expansion serial bus
- Supply power: 24 V DC from backplane
- Operating temperature: 0 °C to +60 °C
- Mounting: Standard 35 mm DIN rail
Functional Features Per-channel configurable signal scaling, no hardware jumpers required. On-board 24 V DC loop power supply, eliminates separate external transmitter power. Digital input filtering smooths sampled values, suppresses field electrical noise. Module status LED indicates power, normal operation, and fault state. Hot swap support, module replacement without full system shutdown. Wide operating range, tolerant of industrial plant temperature fluctuations.
Application Scenarios HVAC air handling unit temperature and pressure signal acquisition Small process plant transmitter network integration HC900 system I/O expansion for new production line equipment Spare part replacement for failed analog input modules Package machinery process variable monitoring
Performance Parameters
- Conversion accuracy: ±0.1% full scale
- Full channel update rate: 10 ms
- Common mode rejection ratio: ≥80 dB
- Input impedance: 250 Ω for current input
- Mean time between failures: 500,000 hours
Material Composition ABS flame-retardant housing 12-bit multiplexed ADC chip TVS surge protection diodes Removable screw terminal block Gold-plated backplane connector DIN rail mounting clip
Structural Features Narrow rectangular DIN-rail mount housing. Front removable terminal block for 8-channel field wiring. Side expansion bus connector mates to adjacent HC900 CPU or I/O modules. Front panel power and fault status LEDs. Integral DIN rail locking clip.
Working Principle Field transmitter signals connect to input terminals. On-board 24 V loop supply powers the connected field transmitter. 4–20 mA current passes through precision sampling resistors to the 12-bit ADC, converting analog current values to digital counts. The module packages channel data into serial bus frames, transmitted to the HC900 CPU over the expansion backplane. Digital filter averages consecutive samples to reduce measurement noise.
Installation Requirements Clip the module to the DIN rail next to the HC900 CPU. Connect expansion bus connector between adjacent modules. Wire field transmitters to labeled channel terminals. Configure input scaling in HC900 Control Builder software. Verify channel values read correctly after power-up.
Usage Notes Never apply AC line voltage to input terminals, high voltage destroys the ADC input circuit. Use shielded cable for transmitter wiring to reduce electromagnetic interference. Removable terminal blocks must be fully seated; loose connections cause channel dropout. Route analog wiring separately from high-power cable trays, maintain 20 cm separation.
