Gmr32b Phase Controller Manual [new] May 2026

The GMR32B Phase Controller is a precision instrument designed for industrial power management. This guide provides a comprehensive overview of its installation, configuration, and operation. ⚡ Overview of the GMR32B

The GMR32B is a microprocessor-based power controller. It manages electrical loads by regulating the phase angle of the power supply. Primary Function: Precise voltage and current control.

Common Uses: Industrial heaters, ovens, and motor speed control.

Key Benefit: High energy efficiency with minimal harmonic distortion. 🛠️ Installation and Wiring

Proper installation is critical for safety and device longevity. Mounting the Unit Install in a well-ventilated enclosure. Ensure vertical mounting for heat dissipation. Keep clear of high-moisture or dusty areas. Electrical Connections

Main Power: Connect the L1, L2, and L3 phases to the designated input terminals.

Load Connection: Attach the resistive or inductive load to the output ports.

Control Signals: The unit typically accepts 4-20mA, 0-10VDC, or manual potentiometer inputs. ⚙️ Configuration and Settings

The GMR32B allows for fine-tuning based on specific application requirements. Phase Angle Control

Adjusting the phase angle determines the point in the AC cycle where the thyristor triggers. Lower Angle: Decreased power output. Higher Angle: Increased power output. Soft Start Function This feature prevents sudden current surges during startup. Set the Ramp Time to protect sensitive heating elements. Gradually increases voltage from zero to the set point. Current Limiting

Protect your equipment by setting a maximum current threshold. Access the internal DIP switches or digital menu. Calibrate the limit based on the load's rated amperage. 🔍 Troubleshooting Common Issues

If the unit is not performing as expected, check the following: Potential Cause Blown internal fuse Replace fuse with correct rating Overheating Poor ventilation Check fan and clearance Erratic Control Signal interference Use shielded control cables Status LED Red Input phase loss Verify all incoming power lines 🛡️ Maintenance and Safety

Regular Inspections: Check for loose terminal screws every six months. Dust Removal: Use compressed air to clean heat sinks.

Safety Warning: Always disconnect the main power source before servicing the unit.

(also known as the COCIS or Ubersweet GMR-32B) is a three-phase power supply monitor relay designed to protect industrial equipment like motors, pumps, and central air conditioning compressors from electrical faults. It monitors for phase loss, reverse phase (incorrect sequence), over-voltage, and under-voltage. Technical Specifications According to documentation from retailers like MUNEFE on Amazon AliExpress typically includes the following specs: Rated Voltage:

Standard 380VAC (variants exist for 220V, 400V, 415V, 440V, and 460V). Operating Frequency: Contact Form:

Two Normally Open (NO) and Two Normally Closed (NC) contacts, which are electrically inseparable. Contact Capacity: 250VAC 6A or 30VDC 3A. Power Consumption:

Standard HT35 (35mm) DIN rail or direct screw mounting via M4 holes. Dimensions: 79 x 23 x 79 mm (approx. 3.11 x 0.91 x 3.11 in). Installation and Wiring gmr32b phase controller manual

The GMR-32B is a "plug-and-play" device intended for the power-supply side of a circuit; it

be installed on the output side of a variable frequency drive (VFD). Amazon.com Input Connection:

Connect the three-phase power lines (L1, L2, L3) to the designated input terminals. For certain models, terminal 1 is used for the R phase, terminal 3 for the B phase, and terminal 5 for the Y phase. Output Connection:

Wire the output terminals (NO, NC, COM) to the motor contactor coil or the motor starter circuit. Wire Gauge:

Use insulating copper wire with a cross-section of 1.0~2.5mm. Status Indicators and Fault Diagnosis The unit features five LED indicators to display real-time status: Amazon.com Required Action Power is within parameters and phase sequence is correct. None; equipment is safe to operate. Phase Loss

One or more phases are missing or there is a voltage imbalance. Check incoming power lines and fuses. Reverse Phase The R, S, T phase sequence is incorrect. Swap any two incoming power lines to correct sequence. Overvoltage Voltage exceeds the safe rated threshold. Check for utility issues or transformer settings. Undervoltage Voltage is too low for safe operation. Reduce load or check for upstream voltage drops. Troubleshooting Common Issues Nuisance Tripping:

Often caused by loose connections at the input terminals mimicking a phase error. Ensure all screws are tightened. Intermittent Faults:

Environmental factors like high humidity or high harmonics can affect performance. The "Smart" series variant of the GMR-32B is specifically built for these harsher conditions. Failure to Trip:

Inspect for welded internal contacts or mechanical debris if the relay fails to disconnect power during a known fault. For specific part numbers such as the

, you can find replacement units and technical details on sites like Do you need a wiring diagram

for a specific application, such as an air compressor or an elevator system?

Phase Reversal Protection: Automatically detects if phases are wired in the wrong sequence, preventing motors from running in reverse and causing mechanical damage.

Phase Failure (Loss) Detection: Shuts down the system if one of the three phases is lost to prevent "single-phasing," which can burn out motors.

Voltage Imbalance Monitoring: Monitors for significant voltage differences between phases that could lead to overheating. Technical Specifications

Contact Configuration: Equipped with two Normally Open (NO) and two Normally Closed (NC) contacts. Connection Capacity: AC: 250VAC at 6A. DC: 30VDC at 3A.

Mounting: Typically designed for standard 35mm DIN rail mounting for easy installation in control panels.

Calibration: Known for being a "plug-and-play" device that often requires no complex manual calibration, allowing for quick deployment. Status Indication The GMR32B Phase Controller is a precision instrument

Most models include LED indicators on the front face to show: Power Status: Green LED indicating the unit is energized.

Fault Status: Red LED indicating a phase failure or incorrect sequence.

For detailed wiring diagrams or specific timing adjustments, you can often find digital copies of the GMR32B Phase Controller Manual or similar verified documentation through technical resource hubs.

The GMR-32B Phase Controller (also known as the COCIS GMR-32B) is a monitoring relay designed to protect industrial equipment like motors, air compressors, and elevators from electrical faults. It provides precise detection for phase sequence (reverse phase), phase loss, overvoltage, and undervoltage. Key Specifications

Rated Voltage: Typically 380V AC (supports industrial levels like 220V, 440V, and 460V at 50/60Hz).

Contact Form: Two normally open (NO) and two naturally closed (NC) contacts, electrically inseparable. Connection Capacity: 250V AC 6A or 30V DC 3A. Dimensions: Roughly

Mounting: Standard 35mm DIN rail (HT35) or screw mounting via two M4 holes. Visual Status Indicators (LEDs)

The GMR-32B features five LED indicators to communicate the system's status at a glance: Normal: Indicates healthy power and correct phase sequence.

Phase Loss: Lights up if any phase (L1, L2, L3) is missing or if there is a three-phase voltage imbalance.

Reverse Phase: Signals that the R, S, T phases are connected in the wrong sequence.

Overvoltage: Activates when input voltage exceeds safety thresholds.

Undervoltage: Activates when input voltage drops below stable operating levels. Wiring and Installation

Understanding the GMR-32B Phase Controller : A Comprehensive Guide COCIS GMR-32B Phase Sequence Relay

is a specialized protection device designed to safeguard three-phase equipment—such as central air conditioners, industrial motors, and elevator systems—from electrical faults

. By monitoring the order and stability of the incoming power supply, it prevents catastrophic mechanical failures before they happen. Key Functions and Benefits

The GMR-32B acts as a "security guard" for your machinery, offering several layers of protection: Phase Sequence Protection

: It ensures the motor only runs when the power sequence is correct (e.g., A-B-C). If phases are reversed, it cuts power to prevent the motor from spinning backward, which could strip gears or damage bearings. Over-Voltage & Under-Voltage Protection —End of manual— If you want

: The relay monitors for voltage fluctuations. If the supply exceeds or drops below safe thresholds (typically around 380VAC), it isolates the circuit to prevent internal component burnouts. Automatic Restoration

: In many applications, once the power sequence or voltage returns to normal, the protector can automatically restore power, ensuring minimal downtime for home appliances. Technical Specifications According to listings on AliExpress , the GMR-32B typically features: Rated Voltage : 380V AC. Operating Range : 300–400V at 50/60Hz. Contact Form

: Two normally open (NO) and two normally closed (NC) contacts. Connection Capacity : 250VAC 6A or 30VDC 3A. Dimensions : Approximately 79mm x 23mm x 79mm.

: Often compatible with standard DIN rails for easy control panel integration. Installation Basics While specific manual steps vary by manufacturer (such as ), general installation involves: Wiring the Three Phases

: Connect the primary L1, L2, and L3 lines to the relay's input terminals. Control Circuit Integration

: Link the relay's NC/NO contacts to your motor starter's control coil. Verification

: Upon powering up, a green LED usually indicates a correct phase sequence. A red LED often signals a fault, such as phase reversal or loss. Why You Need One

If you are maintaining a central HVAC system or industrial manufacturing equipment, a phase relay like the GMR-32B is an essential investment. Technicians at AliExpress

note that these devices frequently solve recurring tripping issues and prevent the destruction of sensitive motor windings during grid fluctuations. wiring diagram

for a specific brand of this controller, or do you need help troubleshooting a current fault light? AI responses may include mistakes. Learn more GMR-32B Phase controller, 300-400V 50/60HZ - JIEFENG

GMR-32B. Jiefeng Code : JDQ-GMR-32B. Color : Black. Lead Time : 3 Days. Add to basket Stock: 1000.

4. Wiring the GMR32B – Terminal by Terminal

Below is a typical terminal assignment for a single-phase GMR32B. Always verify with the sticker on your specific unit.

| Terminal | Label | Function | |----------|-------|-----------| | 1 (L1) | LINE | AC line input (R phase) | | 2 (T1) | LOAD | To load (heater, lamp, etc.) | | 3 | COM | Common for control signal | | 4 | IN+ | 4–20 mA or 0–10 V input (+) | | 5 | ALM+ | Alarm relay NO (normally open) | | 6 | ALM- | Alarm relay common | | 7 | RST | Reset input (momentary to common) | | 8 | +10V | 10 VDC reference for potentiometer | | PE | Ground | Protective earth (chassis) |

5. Configuration DIP Switches & Jumpers

Inside the flip-open front cover, you will find a 6-position DIP switch. Configure before power-up.

| Switch | Function | OFF (default) | ON | |--------|----------|---------------|-----| | 1 | Input type | 4–20 mA | 0–10 V | | 2 | Source | External | Internal (+10V) | | 3 | Firing mode | Phase-angle | Zero-cross burst | | 4 | Feedback | Voltage (open loop) | Current (closed loop, requires external CT) | | 5 | Soft start | Disabled (0 sec) | Enabled (2 sec ramp) | | 6 | Alarm action | Latched (manual reset) | Auto-reset (when temp <70°C) |

Recommendation: For most heating loads, set S1-3 = OFF (phase-angle), S1-4 = OFF, S1-5 = ON. Burst firing (S1-3=ON) reduces RF interference but may cause flicker in incandescent lamps.

6. Operating Modes Explained

GMR32B Phase Controller — User Manual (concise, proper text)

Product: GMR32B Phase Controller
Purpose: Automatic control and protection of three-phase electric motors and loads, ensuring proper phase sequence, phase presence, voltage imbalance protection, and automatic phase switching/transfer.

1. Safety

• Read all instructions before installation or operation.
• Qualified personnel only: installation, wiring, and maintenance must be performed by a licensed electrician or qualified technician.
• Disconnect power before wiring or servicing. Lockout/tagout procedures must be used.
• Follow local electrical codes and standards.
• Do not expose the controller to water, corrosive atmospheres, or explosive environments.
• Use proper fuses or circuit breakers sized for connected loads.
• Do not operate a damaged device.

2. Specifications (typical)

• Supply voltage: 3-phase 380–480 VAC (nominal), 50/60 Hz.
• Control supply tolerance: ±10%.
• Current sensing: external CT or internal sensing per model variant.
• Switching elements: internal contactors/relays or dry contacts for external contactor control.
• Protection functions: phase sequence, phase loss, phase under/over-voltage, unbalance, time-delayed make/break, motor restart delay, soft transfer.
• Operating temperature: -10°C to +55°C.
• Mounting: DIN-rail or panel mount depending on version.
• Indicators: LED for power, phase presence, fault, and bypass/auto/manual status.
• Dimensions and weight: refer to product label or datasheet for exact values.

3. Front-panel controls and indicators

• Power (PWR) LED: indicates controller supply present.
• Phase LEDs (L1, L2, L3): indicate each phase presence and correct sequence.
• Fault LED: indicates a protection trip or fault condition.
• Mode selector: Auto / Manual / Bypass (if provided).
• Time adjustment knobs or buttons: set delay times for phase loss/recovery, transfer delays, and restart inhibit.
• Reset/Test button: manual reset or functional test of outputs.

4. Terminals and wiring

• Main power terminals: connect incoming three-phase lines to L1, L2, L3 (line side) and outgoing load terminals T1, T2, T3 if integrated contactors are present. Respect phase labeling.
• Neutral terminal (N): only if the controller requires neutral for auxiliary supply — follow the model’s wiring diagram.
• Control supply terminals: if separate low-voltage control is required, connect the provided control supply (e.g., 24 VAC/DC or 110/230 VAC) to the appropriate terminals.
• Output relay/dry contacts: COM, NO, NC terminals for remote alarm, starter enable, or transfer control. Wire external contactors through these contacts if required.
• Earth/Ground: connect protective earth to the ground terminal.
• Auxiliary inputs: terminals for remote start/stop, interlocks, or bypass signals — wire per schematic.
• Current transformer (CT) inputs: if using external CTs, connect secondary leads to designated terminals; observe polarity.
• All wiring must be tightened to the specified torque and insulated appropriately. Use ferrules on stranded wire.

5. Operation and settings

• Initial checks: verify supply voltage, correct phase sequence, proper wiring, and tight connections before applying load.
• Mode selection: Auto mode allows automatic detection and switching; Manual mode permits manual control of outputs; Bypass mode (if present) bypasses protection (use with care).
• Delay settings: set phase loss/phase recovery delays to prevent nuisance trips from transient disturbances (common settings: 1–10 s for loss, 5–30 s for recovery).
• Voltage/unbalance thresholds: set trip thresholds according to motor/load ratings (e.g., under-voltage trip at 85–90% of nominal, unbalance trip at 10–15%).
• Restart inhibit: set lockout time after a fault to prevent rapid cycling (typical 30–300 s).
• Phase transfer: on loss of preferred phase, the controller can switch to an alternate source after verification delays; set transfer and retransfer timings to avoid load disturbance.

6. Protection behavior and fault indications

• Phase loss: If any phase is absent beyond the configured delay, outputs are disabled and the Fault LED lights.
• Phase sequence: Incorrect sequence prevents starter enabling; correct sequence must be present for operation.
• Under/Over-voltage: If voltage falls below or rises above configured thresholds, the controller trips.
• Voltage unbalance: Excessive unbalance triggers trip to protect motors.
• Overcurrent (if supported): trips when current exceeds threshold or sustained overload condition.
• Manual reset: After a trip, press Reset (or cycle supply) to clear faults once the cause is corrected.

7. Testing and commissioning

• Verify wiring against the device wiring diagram.
• Power the controller only after verifying that fuses/circuit breakers are in place.
• Perform functional test: with no load connected, simulate phase loss, phase reversal, and voltage variation if safe to do so, and confirm LEDs, alarms, and outputs operate as expected.
• Confirm automatic transfer behavior between phases/sources under controlled conditions.
• Log and record initial settings for maintenance reference.

8. Maintenance

• Periodically inspect terminals for tightness and signs of overheating or corrosion.
• Clean enclosure and vents; keep free of dust and moisture.
• Test indicators and trip functions at scheduled intervals (e.g., annually or per site procedures).
• Replace worn or damaged parts only with manufacturer-approved components.
• Store spare fuses/relays and the product manual on site.

9. Troubleshooting (common issues)

• No power to controller: check supply fuses, breakers, and incoming voltage.
• Phase LED not lit or Fault LED on: check phase presence and sequence, correct wiring, and voltage levels.
• Controller trips repeatedly: check for intermittent supply issues, loose connections, overloads, or incorrect delay settings.
• Outputs do not energize in Auto: verify mode selector, remote start signal, and that no active fault is present.
• Unexpected transfer between phases: examine transfer delay settings, phase voltage stability, and any configured priority source settings.

10. Wiring examples (summary)

• Three-phase supply to controller: L1, L2, L3 → Controller L1-L3.
• Controller outputs to contactor coil: Controller NO → Contactor coil → Neutral (or return), coil other side to supply per local wiring rules.
• Alarm relay: COM → Alarm device → supply; NO used for alarm-on-fault or NC for alarm-on-normal as required.
  (Refer to product-specific wiring diagrams for exact terminal numbers and connections.)

11. Specifications and replacement parts

• Use only manufacturer-specified replacement parts (contactors, fuses, CTs).
• For accurate dimensions, wiring numbers, and detailed electrical ratings consult the product datasheet or label on the unit.

12. Disposal and environmental

• Dispose of the device according to local electronic waste regulations.
• Recycle packaging materials where possible.

13. Manufacturer support

• For product-specific wiring diagrams, exact electrical ratings, firmware/version notes, and certified replacement parts, consult the official datasheet and the manufacturer technical support.

—End of manual—

If you want, I can convert this into a printable PDF, create a shorter quick-start sheet, or produce model-specific wiring diagrams if you provide the GMR32B datasheet or photos of the terminal labeling.

4. Configuration & Setup

The Definitive Guide to the GMR32B Phase Controller: Manual, Operation, and Troubleshooting