DRN3

Supported Applications

The ACI DRN3 series is an interface device designed to allow microprocessor control of a variable resistance. It directly replaces a variable resistance controller and simulates the action of a slide wire or rotary potentiometer. The unit accepts Analog, Pulse, or Floating Point input signals (including triac) and converts them into a proportional resistive output.

Operating Conditions & Performance

The DRN3 operates within an ambient temperature range of 35 to 120°F (1.7 to 48.9°C) with humidity between 10 to 95% non-condensing. Storage is supported from -20 to 150°F (-28.9 to 65.5°C). The device features a resolution of 256 Steps (No wrap around), and the time response full scale is about 6 seconds.

Input signal capabilities include:

• Voltage Signals: 0 to 5 VDC, 1 to 5 VDC, 0 to 10 VDC, 2 to 10 VDC, 0 to 15 VDC, and 3 to 15 VDC @ 10,000Ω.
• Current Signals: 0-20 mA and 4 to 20 mA @ 250Ω.
• Pulse Sources: Relay Contact Closure, Transistor, or Triac with signal levels of 7-30 VDC or 10-26.4 VAC @ 750Ω.

The unit is powered by 24 VAC +/- 10% or 24 VDC +25% / -8%, drawing a maximum of 250 mA supply current.

Fail-Safe and Digital Outputs

• Fail-Back: The DRN3.1 will automatically fail-back to 0 Ohms upon power loss; control reverts to the original controller signal if supply power is lost.
• Digital Output Type: Form "C" Relays with a contact rating of 2A @ 24 VDC and 0.5A @ 240 VAC.

Configuration Options

The series supports extensive configuration options for resistance output ranges, firmware versions, and mounting styles to accommodate specific control requirements.

Resistance Output Networks

Standard resistor networks are available in various ranges with specified wattage and tolerance:

• RN (0-135) Ω: 3W, 5% Tolerance
• RN (0-270) Ω: 3W, 5% Tolerance
• RN (0-500) Ω: 3W, 5% Tolerance
• RN (0-1K) Ω: 0.25W, 5% Tolerance
• RN (0-10K) Ω: 0.25W, 5% Tolerance
• RN (0-15K) Ω: 0.25W, 5% Tolerance
• RN (0-20K) Ω: 0.25W, 5% Tolerance

The series also supports custom resistance ranges upon request.

Firmware and Input Configuration

Different firmware versions support distinct pulse ranges and floating point rates of change:

• Version #1 (Chip 0052Y0H.HEX): Supports Pulse Ranges of 0.02-5.0s, 0.1-25.5s, or 0.59-2.93s; Floating Point Rates of Change at 30, 60, and 90 seconds.
• Version #2 (Chip 0054Y0B.HEX): Supports Pulse Ranges of 0.1 to 10.0s or 0.023 to 6.0s; Floating Point Rates of Change at 45, 120, and 240 seconds.
• Duty Cycle Version #4 (Chip 0305Y1A.HEX): Supports Pulse Range of 0.1 - 10 sec.

Housing and Mounting

The device features a Polyvinyl Chloride (PVC) snaptrack with UL94 V-0 flammability rating. Dimensions are (L) 5.00" x (W) 3.23" x (H) 1.00" (127.00 x 81.99 x 25.40 mm). Electrical connections utilize 45° Captive screw Terminal Blocks accepting wire sizes from 12 AWG to 22 AWG.

Accessories

• A/DRC 4.69 X 3.25: DIN Rail Adapter Kit for mounting flexibility.
• A/D0008 (142583): Transient Voltage Suppressor, Bi-directional, 56 VAC/DC, 1500W.

Key Product Differences

The DRN3 series is distinguished by its configurable input types and resistance output networks. The primary model variations are defined by the firmware version (Version #1 vs Version #2) which dictates supported pulse ranges and floating point rates of change.

• DRN3.1: Standard configuration with specific jumper settings for Analog, Pulse, or Floating Point inputs as detailed in the ordering grid.
• Resistor Networks (RN): Variants are identified by their resistance range (e.g., RN 0-1K vs RN 0-20K) and wattage ratings. Custom ranges outside standard tables require direct consultation with ACI.