YHM-1112 MODBUS to HART Module

MODBUS to HART module for 2-wire, 3-wire or 4-wire transmitters, with customization services available

Use Case

xxxxxxxxx

Product Details

The HART protocol complies with FCG certification testing standards
TTL 3.3V level MODBUS interface

25mmx25mm ultra-compact form factor design
Provide Windows configuration software and DD files

Supports up to 6 device variables
Supports dynamic variable mapping configuration

Built-in automatic unit conversion program
Supports register calibration functions (such as setting the flow coefficient of the flowmeter, etc.)

YHM-1112-2 (2-wire version) can output a 3.3V/12mA power supply to the base plate (when powered by 24V/300Ω and with a loop current of 3.7mA)
YHM-1112-2 (2-wire version) HART bus interface with built-in reverse polarity protection diode and TVS protection
The YHM-1112-3 (3-wire version) current output interface is built with reverse current protection and TVS protection.

Four-layer PCB design, featuring high precision and strong anti-interference capability

Project	Specifications
Bus Power Supply（YHM-1112-2）	10～33V
bus interface（YHM-1112-2）	Two-wire system 4-20mA + HART, with reverse connection prevention and TVS protection
Output Power Supply (YHM-1112-2)	3.3V/12mA, ripple VRMS ≤ 1mV (when powered by 24V/300Ω and loop current is 3.7mA)
Power Supply (YHM-1112-3)	8-33V
Bus Interface (YHM-1112-3)	Three-wire system 4-20mA + HART current output, with reverse current prevention and TVS protection
Modbus Interface	TTL (supporting MODBUS RTU master communication protocol)
Quarantine	The bus and Modbus interface are not isolated
Battery	Under typical operating conditions, the battery lasts for over 10 hours and supports external standalone charging.
Operating Temperature	-40 ～ 85 ℃
Operating Humidity	(5～95)%RH
Storage Temperature	-55 ～ 105℃
Startup Time	≤1 second
Last Updated	0.2 seconds
Damping Adjustment	Time constant: 0 to 32 seconds
Alarm Signal	High/Low alarm current: 21.75mA/3.7mA; Upper/Lower limit current: 20.8mA/3.8mA
Current Accuracy	0.05% FS (at room temperature)
Current Temperature Drift	30ppm
Intrinsic Safety Rating	Ex ia IIC T4/T6 Ga compliant
Electromagnetic Compatibility	Combined with the base plate, equipment meeting the following requirements can be designed and implemented: Meets the immunity requirements for industrial sites specified in GB/T 18268.1-2010 Electromagnetic Compatibility Requirements for Electrical Equipment for Measurement, Control and Laboratory Use — Part 1: General Requirements