Selection and Networking of Beckwith M-2001C Digital Voltage Regulating Controller

During reverse power detection, the REV PWR LED on the panel lights up and can trigger programmable alarm contacts.

2.4 Voltage Limit and Runback

Overvoltage/undervoltage limit: independently adjustable 95~135V, with a step size of 0.1V.

Fallback dead zone: Adjustable from 1 to 4V above the overvoltage limit, and forced voltage reduction when the voltage exceeds the "overvoltage limit+dead zone".

Tap position limit: Users can set upper and lower limits to prevent exceeding the mechanical allowable range of the transformer.

2.5 Voltage Reduction

Support three independent voltage reduction steps, each step ranging from 0% to 10% (based on the center of the belt), with a step size of 0.1%. Add a "voltage drop shutdown timer" (1-999 minutes, 0=disabled), which can automatically release the voltage drop command initiated by communication, suitable for energy-saving cycles or timed voltage drop scenarios.

Parallel operation plan

M-2001C supports multiple parallel connection methods to adapt to different transformer quantities and hardware configurations:

Circulating Current Method: Standard method, requiring the use of M-0115A parallel balancing module. Each controller detects the circulating current through circulating current CT, and M-0115A generates a correction signal to be sent to the circulating current input, achieving tap balance. This method is suitable for parallel connection of multiple transformers (more than two).

Δ VAR method:

Δ VAR1: M-0115A is also required, based on reactive power deviation adjustment, suitable for situations where reactive circulating current is the main contradiction.

Δ VAR2: No M-0115A required, only suitable for parallel connection of two transformers, achieves coordination through communication exchange of reactive power information, and has lower hardware simplification costs.

External Master Slave: Implement command following for a single host controller through external circuits (consult manufacturer).

Important reminder: Except for Δ VAR2, it is recommended to configure overcurrent protection (such as M-0127A) for all other parallel connections to prevent abnormal circulating current from damaging the transformer.

Tracking of tap position

Accurate tap position knowledge is a prerequisite for many advanced features such as returning the neutral point, reverse adjustment, and position limits. M-2001C provides multiple tracking methods:

Transformer LTC: M-2025B (D) current loop interface module and M-2948 rotary position sensor (or compatible with Incon 1250B) need to be selected. The sensor provides a 4-20mA signal, which is converted by the interface module and sent to the controller. The M-2948 series supports forward/reverse rotation, 9 °/10 ° per gear, and multiple tap quantities (16~32 gears) configurations.

Single phase voltage regulator: usually uses the "Motor Direct Drive KeepTrack" logic to maintain tap position counting without the need for external sensors.

The controller is equipped with two built-in counters: a main counter (which can be preset) and a resettable counter, supporting X1 (on-off count once) or X2 (on-off or on-off count once) counting modes, and has a counting window anti shake function.

Communication and networking capabilities

The communication configuration of M-2001C varies by model:

COM2 (front panel): All models come standard with RS-232 and only support BECO 2200 protocol for local parameter settings and firmware upgrades.

COM1 (top): Comprehensive and Base RS models are available, with optional RS-232, RS-485, or fiber optic (ST interface), supporting multiple protocols such as BECO 2200, BECO 2179, Cooper 2179, DNP3.0, MODBUS, etc.

COM3 (Ethernet): Only available for Comprehensive models, with RJ-45 10Mbps port, supporting DNP over TCP/IP, BECO 2200 over TCP/IP, and MODBUS over TCP/IP.

Network topology: Supports point-to-point direct connection, modem remote dialing, RS-485 multi station bus (up to 200 addresses, requiring 120 Ω terminal resistance at the end), and fiber optic loop. TapTalk software can implement broadcast commands (such as voltage regulation locking, three-step voltage reduction), alarm recognition, selective voltage regulation, and parameter modification.

SCADA heartbeat function: using DNP protocol to detect the presence or absence of SCADA communication, automatically switching between two sets of settings to ensure that it still operates according to preset security policies in case of disconnection. The manual heartbeat timer allows for temporary placement in manual mode through communication and automatically returns to automatic mode according to the set time, making it convenient for remote operation and maintenance.

Data recording and analysis

M-2001C has powerful built-in data management capabilities:

Real time measurement: local voltage, load center voltage, current, active/reactive/apparent power, power factor, frequency.

Demand measurement: Record the maximum current and maximum power (including corresponding power factor) with time stamps at a 15/30/60 minute cycle.

Drag Hands: Slide the window for 32 seconds to record the maximum/minimum voltage with a time stamp.