Description

Used product. Original BENDER RCMA177P2-S electronic module, article number B94042088, used as an AC/DC residual current monitoring module inside electronic equipment and photovoltaic inverters.
The photographed component is an RCM (Residual Current Monitoring) module equipped with an integrated toroidal sensor and measurement electronics. The board detects differential/residual current in the monitored circuit and provides the corresponding signal to the inverter control electronics.
The component is associated with applications in SMA SMC 9000TL, SMC 10000TL, and SMC 11000TL 220 V inverters, where the module serves as the BENDER Sunny AC Sensor Card for residual current monitoring.
Important: the exact model visible on the board is RCMA177P2-S, code B94042088. The designation RCMA178P-S / B94042090 identifies a different model and must not be used to identify this board.

⚙️ Technical Specifications

• Manufacturer: BENDER
• Model: RCMA177P2-S
• Article number: B94042088
• Type: electronic RCM – Residual Current Monitoring module
• Function: differential/residual current monitoring
• Sensitivity: AC/DC – all-current sensitive
• Sensor: integrated toroidal current transformer
• Measurement electronics: integrated on the PCB
• Visible microcontroller: Microchip PIC16F670
• PCB: L108207A / L108207B
• Software: D0257 V1.0
• Marking: A: B94042088
• Visible S/N: S:1010507419
• Rear marking: RCMA177P2-S
• Visible certification: CE
• Connections: multipole connectors for interfacing with the equipment.
• Construction: electronic PCB with integrated toroidal sensor and processing circuits.

⚡ Function in the Electrical System

The BENDER RCMA177P2-S is not simply a current transformer, but a complete electronic residual current detection module.
The circuit being monitored passes through the toroidal sensor. Under normal conditions, the sum of the currents detected by the toroid is substantially balanced. If current flows through an unintended path, for example toward earth, a differential/residual current is detected.
The integrated electronics processes the signal from the sensor and makes it available to the inverter control system.
RCMA technology is particularly important in electronic inverters because it allows residual currents containing both AC and DC components to be detected.

☀️ SMA SMC Application

The module is intended for integration into the monitoring system of SMA SMC 9000TL, SMC 10000TL, and SMC 11000TL 220 V inverters.
In this application, the component is identified as the BENDER Sunny AC Sensor Card and is used for residual current monitoring within the inverter system.
The signal from the module is used by the inverter control electronics to detect possible abnormal residual current conditions and, according to the protection logic provided by the equipment, may contribute to placing the inverter in a safe state or shutting it down.

🔧 Faults, Errors & Symptoms

A malfunction of the RCMA177P2-S may cause abnormalities in the inverter's residual current monitoring system.
Possible symptoms:

• residual/differential current alarm;
• indication of leakage to earth;
• inverter startup failure;
• shutdown during operation;
• apparently unjustified protection trips;
• incorrect or implausible residual current values;
• absence or instability of the measurement signal;
• intermittent alarms;
• abnormalities during photovoltaic production;
• inverter entering protection mode after a certain period of operation.
  Attention: a residual current abnormality does not automatically indicate a BENDER fault. The cause may be an actual leakage in the PV field, DC cables, connectors, insulation, EMC filters, power stage, or other inverter circuits.

🛠️ Checks & Possible Repair

The module can undergo electronic diagnostics by checking:

• board power supplies;
• toroidal sensor;
• winding continuity;
• input circuits;
• analog measurement circuits;
• signal processing circuit;
• PIC16F670 and its power supplies;
• SMD and discrete components;
• solder joints;
• connectors;
• output signal toward the inverter;
• measurement correspondence with a reference instrument.
  Simply checking the continuity of the toroid is not sufficient to establish correct module operation, since the fault may also affect the measurement and signal-conditioning electronics.

🏭 Construction & Product Condition

The board is used and shows normal signs of previous installation and handling.
The component appears complete with toroidal sensor, electronic components, integrated circuits, microcontroller, and connectors. No major structural damage or extensive burns are evident from the photographs.
The original markings BENDER, RCMA177P2-S, B94042088, D0257 V1.0, L108207A, and L108207B are visible.
The sale concerns the component in the condition shown in the photographs. Without a specific test, electrical operation is not declared.

🌐 Applications

The BENDER RCMA177P2-S B94042088 is suitable for residual current monitoring applications in:

• SMA SMC 9000TL 220 V;
• SMA SMC 10000TL 220 V;
• SMA SMC 11000TL 220 V;
• photovoltaic inverters;
• transformerless inverters;
• electronic conversion systems;
• equipment where AC/DC residual current components may be present.

🛡️ Safety

The module is intended for use inside electrical equipment that may operate with high AC and DC voltages.
Installation, diagnosis, and replacement must be carried out exclusively by qualified personnel, with the equipment completely de-energized and secured.
The RCMA177P2-S is a monitoring device and must not be considered an autonomous protection device. Before replacement, any actual leakage to earth in the inverter or photovoltaic field must also be checked.

📦 Package Contents

1 × BENDER RCMA177P2-S B94042088 – Sunny AC Sensor Card, AC/DC RCM module with integrated toroidal sensor, as shown in the photographs.

🚀 Final Description

The BENDER RCMA177P2-S B94042088 is an AC/DC RCM module with an integrated toroidal sensor, used as a BENDER Sunny AC Sensor Card in the residual current monitoring system of SMA SMC 9000TL, 10000TL, and 11000TL 220 V inverters.
The module detects differential/residual currents with AC and DC components and provides the signal required by the inverter electronics to monitor leakage conditions.
It is a specific and important electronic component for the inverter monitoring system. A malfunction may be associated with residual current alarms, leakage-to-earth abnormalities, startup failure, inverter shutdowns, or intermittent indications. Diagnosis must nevertheless distinguish a module fault from an actual leakage present in the system or power stage.