DRP-8555 DIN Strain Gauge to Frequency Converter for Micro PLCs

Supported Applications

The Omega DRP-8500 Series provides low-cost analog I/O solutions for micro PLCs in discrete automation applications requiring one or two analog channels. These modules interface with PLC high-speed counter inputs or pulse outputs, converting various sensor signals into digital frequency pulses compatible with standard logic systems.

Operating Conditions & Performance

The series delivers 12-bit resolution across its conversion functions. Models feature a fixed digital signal pulse width of 50 μsec for high-speed counter inputs. The DRP-8600 sub-series interfaces with low-speed 24 VDC logic inputs, outputting a square wave up to 500 Hz with a 50-50 duty cycle.

Power is supplied at 24 volts nominal. All modules are housed in a plastic case with dimensions of 42 H x 27 W x 96 mmL (1.65 x 1.06 x 3.78") and weigh 85 g (3 oz). Electrical connections utilize screw terminals accepting wire sizes from 22 to 16 AWG.

Configuration Options

The series supports multiple input types including thermocouple, RTD, strain gauge, voltage, current, and frequency. Outputs are provided via isolated floating optocoupler transistors for DC isolation or fully floating output transistors allowing source or sink connection to the PLC.

Input Configurations

• Analog: 4 mA to 20 mA, 0 to 5 Vdc, 0 to 10 Vdc
• Frequency: Ranges from 0 to 5000 Hz and specific bands such as 400 to 2000 Hz or 1000 to 5000 Hz (optocoupler diode input)
• Thermocouple: Type J T/C (0 to 500°C, 0 to 1000°C) and Type K T/C (0 to 500°C, 0 to 1250°C)
• RTD: Platinum RTD -100 to +400°C (100 ohm α = 0.00385), supporting 2 or 3 Wire Connection
• Strain Gage: 0 to 50 mV Differential Signal from full bridge Strain Gage with 10 V excitation provided

Output Configurations

• Analog Output (Frequency-to-Analog): 4 to 20 mA, 0.1 to 5 Vdc, 0.05 to 5 Vdc, 20 mA, and 10 Vdc
• Frequency Output: Ranges include 1,000 to 5,000 Hz, 0 to 5,000 Hz, 100-500 Hz, 0-500 Hz, 10-1100 Hz, and 5 Hz to 630 Hz from floating optocoupler

Key Product Differences

The DRP-8500 Series is designed for high-speed counter inputs with pulse widths of 50 μsec. The DRP-8600 sub-series targets low-speed logic applications, outputting square waves up to 500 Hz.

Specific model variations include:

• Analog-to-Frequency (High Speed): Models such as DRP-8505 convert 4 mA to 20 mA inputs to 1,000 to 5,000 Hz outputs.
• Frequency-to-Analog: Models like DRP-8508 accept frequency inputs (e.g., 1000 to 5000 Hz) and output analog signals such as 4 to 20 mA or voltage ranges including 0.1 to 5 Vdc.
• Sensor-to-Frequency: Dedicated models exist for Type J/K Thermocouples (e.g., DRP-8511, DRP-8512), Platinum RTDs (DRP-8540), and Strain Gages (DRP-8555).
• Low-Speed Pulse Input: The DRP-8600 series includes models like DRP-8605 for 4-20 mA inputs converting to 100-500 Hz outputs.