FUJI NP1AXH8G-TC Input Module | 8 Ch Thermocouple

This input module provides thermocouple measurement capability for FUJI MICREX-SX automation systems. It connects directly to temperature sensors without external signal conditioning. Therefore, it enables precise temperature monitoring for industrial heating and process control applications.

Physical and Analog Specifications

The FUJI NP1AXH8G-TC measures 13.0 cm in length and 9.5 cm in width. Moreover, its module weight equals approximately 0.35 kg for DIN rail mounting. A single 30-pin removable terminal block handles all field wiring connections. Additionally, this module contains eight independent thermocouple input channels.

Parameter	Specification
Brand	FUJI Electric
Full Model	NP1AXH8G-TC
Category	Input Module (Thermocouple)
Dimensions (L x W x H)	13.0 cm x 9.5 cm x 6.0 cm (5.12″ x 3.74″ x 2.36″)
Module Weight	0.35 kg (0.77 lbs)
Primary Interface	1 x 30-pin Removable Screw Terminal Block
Backplane Interface	1 x 48-pin Male Connector (MICREX-SX Rack)
Operating Voltage	24 VDC from Backplane (19.2 to 28.8 VDC)
Power Consumption	3.5 W (Typical)
Analog Input Channels	8 Differential Channels
Input Type	Thermocouple (Direct Connection)
Supported Thermocouples	Type K, J, E, T, R, S, B, N
Input Voltage Range	-10 mV to +70 mV (Thermocouple Range)
Cold Junction Compensation	Internal (Automatic per Channel)
Resolution	16 Bits (0 to 65535 Counts)
Conversion Type	Sigma-Delta
Conversion Speed	50 ms per Channel (400 ms for All 8 Channels)
Absolute Accuracy	±0.25% of Full Scale at 25°C
Accuracy Drift	±0.01% per °C
Common Mode Rejection	120 dB (50/60 Hz)
Normal Mode Rejection	80 dB (50/60 Hz)
Input Impedance	2 MΩ (Typical)
Maximum Input Voltage	±30 VDC (Continuous)
On-Board Components	2 ADC Chips + 8 Signal Conditioning Circuits + 2 Temperature Sensors (CJC) + 8 Protection Diodes + 1 EMI Filter + 1 Voltage Reference IC + 1 Microcontroller
Energy Storage	3 x 220 µF Electrolytic Capacitors (35V) + 3 x 10 µF Tantalum (25V)
Isolation Rating	1500 Vrms (Field to Logic)
Operating Temperature	0°C to +55°C (32°F to 131°F)
Mounting Type	DIN Rail or MICREX-SX PLC Rack
Status Indicators	1 Green LED (Power) + 1 Green LED (Active) + 1 Red LED (Fault) + 8 Green LEDs (Channel Valid)

Thermocouple Input and Cold Junction Compensation

The FUJI NP1AXH8G-TC accepts direct connection from eight common thermocouple types. Specifically, Type K, J, E, T, R, S, B, and N are all supported. In addition, internal temperature sensors provide automatic cold junction compensation per channel. Moreover, the module linearizes each thermocouple signal for accurate temperature readings. Consequently, you do not need external transmitters or signal conditioners for any channel.

High-Density and High-Resolution Features

This input module provides eight thermocouple channels in a single rack slot. For instance, the 16-bit resolution delivers 65,535 discrete counts for precise measurement. In addition, the sigma-delta converter ensures excellent linearity and repeatability. Furthermore, the 50 ms per channel conversion speed suits multi-zone temperature control. Thus, this module handles large heating applications with many zones efficiently.

Noise Rejection and Accuracy Performance

This input module delivers exceptional noise rejection for stable readings. Specifically, the 120 dB common mode rejection eliminates ground loop interference effectively. In addition, the 80 dB normal mode rejection filters 50/60 Hz power line noise. Moreover, the absolute accuracy of ±0.25 percent ensures reliable temperature control. Therefore, the FUJI NP1AXH8G-TC performs reliably in electrically noisy industrial environments.

Energy Storage and Signal Integrity

This input module stores energy using six onboard capacitors for power filtering. Specifically, three electrolytic capacitors smooth the 24 VDC supply for stable ADC operation. In addition, three tantalum capacitors provide high-frequency noise suppression for analog circuits. Furthermore, these capacitors maintain conversion accuracy during brief power interruptions. Thus, this module rejects electrical noise from factory environments effectively.

Installation and Diagnostic Indicators

Eleven LED indicators provide operational status at a glance on this module. First, a green Power LED lights when the 24 VDC backplane supply is present. Second, a green Active LED flashes during normal analog conversion operation. Third, a red Fault LED indicates hardware errors or out-of-range temperatures. Additionally, eight green Channel Valid LEDs illuminate when each channel reads a valid thermocouple signal. Thus, you can diagnose sensor status instantly without external tools.