1. General Information

• Part Number: 0‑52808‑2 (also written O‑52808‑2)

• Manufacturer: Reliance Electric (later ABB Baldor‑Reliance)

• Type: OLVC (Overload / Line Voltage Control) Board

• Function: DC drive monitoring & protection plug‑in card

• Status: Obsolete / legacy; NOS or refurbished only

2. Description

• Rack‑mount plug‑in PCB for Reliance MaxPak Plus / V‑Series DC drives

• Conformal coated PCB, gold‑plated edge connector

• Front panel: 5 LED fault indicators + reset button

• Revision: −2 is a later revision of 0‑52808 / 0‑52808‑1, functionally close with minor component updates

3. Functions

• Overload current monitoring (armature overload trip)

• 3‑phase line voltage supervision (over/under voltage)

• Phase sequence detection (reverse phase trip)

• Field loss protection (field voltage monitor)

• Fault relay output: SPDT contact, 120/240 VAC, 5 A

• LEDs: Arm Volt, Phase Seq, Field Supply, Overload, IET Fault

4. Electrical Specifications

• Power Supply: 115 / 230 VAC (drive internal supply)

• Power Consumption: ≤ 15 VA

• Monitoring Ranges:

  • Armature voltage: 0–500 VDC

  • Field voltage: 0–250 VDC

  • Line voltage: 3‑phase 208–480 VAC

• Isolation: 1500 VAC (signal‑to‑power)

5. Environmental

• Operating Temp: 0 °C to +55 °C

• Storage Temp: −20 °C to +70 °C

• Humidity: 5%–95% non‑condensing

6. Mechanical

• Form Factor: Standard 19” rack plug‑in card

• Dimensions (W×H×D): 120 × 220 × 25 mm approx

• Weight: ~0.34 kg (12 oz)

• Connector: Gold‑plated edge connector (backplane)

7. Compatibility

• Reliance MaxPak Plus DC spindle drives

• Reliance V‑Series DC drives

• Interchangeable with 0‑52808 and 0‑52808‑1 in most systems (revision −2 is more recent)