Description

Description:

The PACIFIC 33VM52-000-29 is a robust, electromechanical 3-phase voltage monitoring relay designed to protect motors, transformers, and other critical electrical equipment from damaging supply anomalies. Manufactured by Pacific Scientific (now part of AMETEK Aerospace & Defense), this device continuously supervises line voltage for undervoltage, overvoltage, phase loss, and severe imbalance—triggering a reliable SPDT output contact to initiate alarms or shutdown sequences.

Built for decades of service in harsh industrial environments, the 33VM52-000-29 combines analog simplicity with mechanical durability, offering a cost-effective, maintenance-free solution where digital relays may be over-specified or vulnerable to EMI.

Application Scenarios:

At a municipal wastewater treatment plant in the Midwest, repeated burnouts of 200 HP sludge pumps were traced to utility-side voltage sags during summer peak demand. The existing control scheme lacked under-voltage protection, causing motors to draw excessive current during low-voltage conditions. Engineers installed the PACIFIC 33VM52-000-29 on each pump starter, setting undervoltage at 85% of nominal with a 2-second delay to ignore momentary dips. Within six months, motor failures dropped to zero. During a grid disturbance caused by a downed transmission line, the 33VM52-000-29 tripped cleanly, its bright red mechanical flag clearly indicating “undervoltage” to maintenance crews—enabling rapid root-cause analysis without diagnostic tools. This blend of reliability, clarity, and ruggedness makes the PACIFIC 33VM52-000-29 indispensable in infrastructure where uptime and simplicity are paramount.

Parameter:

Main Parameters Value/Description

Product Model 33VM52-000-29

Manufacturer Pacific Scientific (AMETEK Aerospace & Defense)

Product Category 3-Phase Electromechanical Voltage Monitoring Relay

Input Voltage Range 120–600 VAC, 50/60 Hz (field-selectable via terminal jumpers)

Protection Functions Undervoltage, Overvoltage, Phase Loss, Severe Voltage Imbalance

Adjustable Setpoints 70–120% of nominal (UV); 105–130% (OV) via calibrated dials

Time Delay 0.5 to 30 seconds (adjustable potentiometer)

Output Contacts 1 SPDT (Form C) electromechanical relay, 10 A @ 250 VAC

Reset Type Manual (push-to-reset button with visual trip flag)

Enclosure Rating NEMA 1 (general purpose), optional NEMA 4X with cover

Mounting Method DIN rail (35 mm) or panel mount (with optional bracket)

Operating Temperature -20°C to +60°C

Certifications UL 508. CSA, CE

Technical Principles and Innovative Values:

True Electromechanical Reliability: The PACIFIC 33VM52-000-29 uses no microprocessors or firmware—eliminating software crashes, cyber vulnerabilities, and battery-backed memory failures common in digital relays.

Visual Mechanical Trip Indication: A bright red flag pops out on fault, providing unambiguous status even during power loss—critical for lockout/tagout (LOTO) and troubleshooting.

Field-Configurable Voltage Range: Via internal jumper settings, the same 33VM52-000-29 unit supports 120V, 240V, 480V, or 600V systems—reducing spare inventory costs.

High Cycle Life & Surge Immunity: Rated for 10 million mechanical operations and tested to IEEE C37.90 standards, the 33VM52-000-29 withstands repeated faults in demanding motor control centers.

Application Cases and Industry Value:

In a food processing facility, the PACIFIC 33VM52-000-29 prevented catastrophic freezer compressor damage during a regional brownout. While digital PLC-based monitors froze due to power supply ripple, the analog 33VM52-000-29 reliably tripped, saving $ 85.000 in equipment and avoiding a 3-day production halt. Similarly, at a mining operation in Chile, the relay’s immunity to dust, vibration, and wide temperature swings ensured consistent performance in remote conveyor drive stations—where maintenance visits occur only quarterly. Users consistently highlight its “install-and-forget” dependability and ease of calibration with basic hand tools.

Installation, Maintenance, and Full-Cycle Support:

Installing the PACIFIC 33VM52-000-29 requires connecting three-phase voltage inputs and wiring the SPDT output to a control circuit or alarm horn. Setpoints are adjusted using front-panel dials, with time delay fine-tuned via a side-mounted potentiometer. No programming or software is needed—making commissioning accessible to electricians without IT support.

Maintenance is minimal: periodic visual inspection of the trip flag and verification of setpoint dials. The manual reset ensures operators acknowledge faults before restart, enhancing safety. The unit is repairable in some cases, but most users replace it as a sealed module due to low cost and high reliability.

Every 33VM52-000-29 we supply is either new surplus from AMETEK-authorized channels or functionally tested to OEM specifications—including voltage accuracy (<±2%), contact resistance (<50 mΩ), and time-delay repeatability. Our technical team provides application engineering support for coordination with contactors, fuses, and modern control systems.

Contact us for a customized solution—whether you need a single PACIFIC 33VM52-000-29 for a critical pump or a fleet-wide rollout across your motor control centers, we deliver proven voltage protection that stands the test of time, environment, and electrical stress.