Technical Parameters Parameter Specification Model Fisher 249 (with suffixes for specific models, e.g., 249R, 249H) Type HART Signal Conditioner / Isolator / Converter Input Signal 4-20 mA, HART digital signal (from a 2-wire HART transmitter) Output Signal 4-20 mA (analog, isolated from input) HART Communication Supports HART 5/6/7 protocol on the input side. Power Supply Typically 18-30 V DC (loop powered or separately powered depending on model). Load Capacity 0-600 Ohms (on the 4-20 mA output loop) Accuracy ±0.05% of span Isolation Input to Output to Power: 1500 V AC (standard) Response Time Typically < 100 ms. Ambient Temperature Limits -4°F to 185°F (-20°C to 85°C) Mounting Standard 35 mm DIN Rail Enclosure Module for mounting inside a control panel cabinet. Typical Functions Signal repeater, Square root extraction, Signal isolator, Signal converter.
