When your site runs with two independent power sources, think dual transformers or a grid + solar export setup, accurate energy measurement gets tricky. Active power depends on both voltage and current (P = V × I × cosφ). If your meter “sees” current from one source but voltage from another, power factor is wrong and your energy totals drift.
SATEC’s new dual Voltage Input Module (VIM) solves this elegantly by giving the BFM II Branch Feeder Monitor a second three-phase voltage input so each load is paired with the correct source, every time.
What the VIM Does (and Why It Matters)
Dual-source accuracy
The VIM adds an extra three-phase voltage input to the BFM II, letting the meter assign each measured load/current to the correct source. That removes the angle/phase ambiguity and restores true active power and energy accuracy under dual-source conditions.
All your circuits on one device
With VIM installed, a single BFM can monitor up to 36 current channels (e.g., 12 three-phase or 36 single-phase circuits, or any mix), replacing a cluster of single meters with one scalable system. Channel-to-source assignment is done in SATEC’s Power Analysis Software (PAS) for quick setup and reconfiguration.
Lower installed cost, smaller footprint
The multi-circuit design was built to simplify and reduce costs – fewer meters to buy, wire, mount and maintain. Adding VIM extends those savings to dual-source sites that used to require multiple meters just to keep measurements straight.
High-Impact Applications
Transformer efficiency, measured directly. Monitor the MV side and LV side with a single BFM + VIM to calculate transformer losses in real time, no extra MV meter required.
Inverter health check for renewables. The BFM measures individual harmonics per current channel up to the 25th, helping you spot failing inverters that often show rising harmonic content before outright failure.
Retrofit without downtime. Using split-core HACS CTs and the BFM’s retrofit-friendly design, you can install and digitalise a substation without a shutdown, accelerating projects and avoiding outage costs.
Built for Substations and Complex Sites
Serious I/O for situational awareness. Up to 72 digital inputs capture external status signals (breakers, relays, access alarms), analogue inputs bring in feeder/transformer telemetry (temperature, oil level), and up to 18 relays can control breakers or raise alarms.
SCADA-ready out of the box. Communicate over TCP, serial, or 4G, and integrate with SCADA systems via IEC 60870-5-101/104, Modbus, or DNP3.0. There’s even a Digital Fault Recorder (BFM-DFR) option to record faults up to 40× In—a cost-effective way to add disturbance visibility.
Revenue metering + PQ insights. Beyond multi-circuit billing (including revenue-class metering), the BFM platform supports individual harmonic analysis and works with SATEC’s High Accuracy Current Sensors (HACS)—solid or split-core from 5A to 3,000A with accuracy up to 0.1%. You can even connect to a 5A secondary from existing protection-relay CTs for ease of retrofitting via SATEC’s HACS / CTs.
Key Benefits at a Glance
Accuracy with two sources: Correct voltage/current pairing eliminates phase-angle errors and protects energy totals.
One system, many circuits: Scale to dozens of loads per BFM, configured quickly in PAS.
Lower cost to deploy: Fewer meters, less wiring, smaller enclosures—and reduced maintenance.
Condition-based insights: Harmonics per channel reveal inverter or feeder issues early.
Substation-grade integration: Rich I/O, open protocols, and optional DFR to close the loop from measurement to action.
Retrofit friendly: Split-core CTs and live-install workflows minimise disruption.
Make Dual-Source Metering Simple
In short, pairing the VIM with the BFM II gives you accurate metering across dual sources, scalable multi-circuit coverage, and substation-ready integration—without the cost and complexity of multiple meters. If you’re planning a retrofit, chasing cleaner energy data, or need tighter SCADA visibility, this is a smart, future-proof step.
Ready to explore your site’s fit? Contact the SATEC team to talk through your application and get a tailored recommendation.
Frequently Asked Questions - Voltage Input Module (VIM)
What problem does the Voltage Input Module (VIM) solve?
Dual-source sites (e.g., two transformers, grid + PV) often mis-pair voltage and current, corrupting power/energy totals. VIM adds a second three-phase voltage input so the Branch Feeder Monitor (BFM) assigns each load to the correct source and keeps measurements accurate.
How many circuits and sources can I meter?
A single BFM with VIM meters up to 36 current channels (e.g., 12 three-phase or 36 single-phase) while handling two independent voltage sources, with source assignment managed in Power Analysis Software (PAS).
Will it integrate with my SCADA and protection?
Yes. Communication over TCP /serial /4G with IEC 60870-5-101/104, Modbus and DNP3.0; up to 72 digital inputs, analogue inputs for transformer telemetry, up to 18 relays for control and an optional Digital Fault Recorder (DFR) for fault recording to 40× In.
