Two generations, eight models: GEN1 local-LCD (BMC series: segmented LCD + 4 buttons, 8–120V wide voltage, optional Bluetooth) and GEN2 Bluetooth smart (BLE APP + RS485). Each generation in 200A / 500A / 1000A / 2000A ranges. True shunt sampling replaces voltage estimation — SOC, voltage, current, temperature and time-remaining on one screen, covering everything from Class B vans to high-power conversions and storage cabinets.
The biggest problem with RV battery gauges is drift over time. Blue Shunt uses true shunt sampling with capacity re-synchronization, so SOC stays accurate long-term. Selection takes two steps: decide how you read the data (GEN1 / GEN2), then size the main circuit current (200A – 2000A).
The base model with a built-in segmented LCD and four buttons: SOC ring, voltage, current, temperature and time-remaining read directly on the unit — no phone or host required. 8–120V wide voltage covers lithium, LiFePO4, lead-acid and NiMH packs. Bluetooth optional.
The smart model with built-in Bluetooth. View SOC, voltage, current, power and history curves directly in the APP; configure capacity, work mode and P1 power supply in the APP — while RS485 (Modbus) still connects to the vehicle system.
Two generations × four current ranges. Ranges are named after the paired shunt's full-scale current; all shunts output 75mV at full scale.
| Gen | Model | Paired Shunt | Continuous Current | Peak Current | Data Reading |
|---|---|---|---|---|---|
| GEN1 | Blue Shunt Gen1 · 200A | 200A / 75mV | 0–140A | ≤200A | Local LCD · BLE APP optional |
| GEN1 | Blue Shunt Gen1 · 500A | 500A / 75mV | 0–350A | ≤500A | Local LCD · BLE APP optional |
| GEN1 | Blue Shunt Gen1 · 1000A | 1000A / 75mV | 0–700A | ≤1000A | Local LCD · BLE APP optional |
| GEN1 | Blue Shunt Gen1 · 2000A | 2000A / 75mV | 0–1400A | ≤2000A | Local LCD · BLE APP optional |
| GEN2 | Blue Shunt Gen2 · 200A | 200A / 75mV | 0–140A | ≤200A | BLE APP · RS485 · LCD panel |
| GEN2 | Blue Shunt Gen2 · 500A (standard) | 500A / 75mV | 0–350A | ≤500A | BLE APP · RS485 · LCD panel |
| GEN2 | Blue Shunt Gen2 · 1000A | 1000A / 75mV | 0–700A | ≤1000A | BLE APP · RS485 · LCD panel |
| GEN2 | Blue Shunt Gen2 · 2000A | 2000A / 75mV | 0–1400A | ≤2000A | BLE APP · RS485 · LCD panel |
⚠ Shunts and meters of different ratings have different internal parameters and must not be mixed. Contact us before ordering to verify battery capacity and maximum main-circuit current.
GEN1 is an "instrument + sampler" local-display solution; GEN2 is a "Bluetooth hub + shunt" smart solution. Each generation has its own independent datasheet.
| Item | GEN1 (Base) | GEN2 (Bluetooth Smart) |
|---|---|---|
| Data reading | Local segmented LCD: SOC ring, voltage, current, temperature, time remaining | Phone BLE APP direct view, plus RS485 and LCD panel outputs |
| Configuration | Four on-unit buttons: CAP / FCV / ZCV / LCA / POV (long-press OK 3 s) | All parameters (CAP, work mode, P1 supply) configured in APP with power-loss memory |
| Bluetooth APP | Optional BLE version connects to the app for monitoring & alarms; standard version has no BLE | Built-in Bluetooth, Swift Loong APP data interaction |
| Operating voltage | 8 – 120V (Li / LFP / lead-acid / NiMH packs) | DC 8 – 60V supply (12 / 24 / 36 / 48V systems) |
| Protection & alarms | Over/under-voltage alarms (settable 8–120V), over-current, over-power, over-temp (55℃); low-capacity buzzer every 10 s, OK to mute | Sampling & communication-side protection with red alarm LED |
| Low power | Auto-sleep with backlight off at low current; 2-min backlight timeout on discharge | Static draw ≤15mA — won't drain the battery during long parking |
| Factory reset | Press [▼] + [▲] together for 5 s | Rear Reset key, long-press 5 s |
| Current ranges | 200A / 500A / 1000A / 2000A | 200A / 500A / 1000A / 2000A |
| Best for | Independent monitoring without a phone; flush-mount dash installation (110 × 60mm cutout) | Single-vehicle conversions, on-site commissioning, phone viewing and self-calibration |
| GEN1 · BMC Series | Specification |
|---|---|
| Product series | BMC series battery coulomb meter (Blue Shunt Gen1), standard & Bluetooth versions |
| Compatible batteries | 8 – 120V Li / LiFePO4 / lead-acid / NiMH packs |
| Current measurement | 0 – 500A (with matching-range sampler) |
| Resolution | Current 0.01A · Voltage 0.1V |
| Accuracy | Voltage ±2% · Current ±5% |
| Temperature range | 0℃ – 100℃ |
| Capacity display | 0 – 100% / 0.01AH resolution · 0 – 999.99AH range |
| Sampling rate | 1 / second |
| Alarm | Over/under-voltage (settable 8–120V); temp alarm 55℃; low-capacity buzzer every 10 s |
| Display & keys | Segmented LCD (SOC ring / V / A / temp / time) + 4 backlit buttons |
| Panel cutout | 110 × 60mm rectangular hole, clip or screw/tie mounting |
| Warranty | 1 year from purchase (non-human-induced issues) |
| GEN2 · Blue Shunt Gen2 | Specification |
|---|---|
| Supply voltage | DC 8 – 60V · system 12 / 24 / 36 / 48V |
| Continuous / peak current | 0 – 350A / ≤500A (500A / 75mV shunt) |
| Battery capacity | 1 – 9999 AH |
| Static draw | ≤15 mA |
| Resolution | Current 1mA · Voltage 0.1V · SOC 1% · Time 1 min |
| Communications | COMM (RJ45 8PIN) RS485 with Modbus protocol |
| Bluetooth | Built-in, APP data interaction |
| Indicators / reset | Red (fault) / Blue (BLE) / Green (run); rear Reset long-press 5 s |
| Operating temperature | -35℃ ~ +65℃ · IP52 (natural cooling) |
| Housing / size | Flame-retardant ABS+PC matte; 106 × 54 × 43 mm / 0.26 kg |
| Customization | OEM / ODM: logo, housing, measurement range and protocol |
Named after the paired shunt's full scale. Selection rule: size by the maximum continuous current the main circuit can see, with about 30% headroom.
| Range | Paired Shunt | Continuous | Peak | Recommended Use |
|---|---|---|---|---|
| 200A | 200A / 75mV | 0–140A | ≤200A | Class B / small RVs, house battery ≤400Ah, inverter ≤1500W |
| 500A (standard) | 500A / 75mV | 0–350A | ≤500A | Mainstream Class C RVs, battery ≤800Ah, inverter 2000–3000W |
| 1000A | 1000A / 75mV | 0–700A | ≤1000A | High-power RVs / parallel battery banks, inverter ≥5000W |
| 2000A | 2000A / 75mV | 0–1400A | ≤2000A | Commercial vehicles, construction machinery, storage cabinets |
Accuracy comes down to two actions: setting CAP correctly and re-synchronizing capacity once. Do these four steps and SOC won't drift.
| Step | Operation |
|---|---|
| 1 · Wiring check | Wire the sampler/shunt and meter as shown. After power-on the display should show voltage, current and SOC. Compare displayed vs actual current (clamp meter); if off, re-check wiring |
| 2 · Set CAP | Known capacity: enter the true value. Unknown (GEN1): preset CAP higher (e.g. 20Ah estimated → set 30Ah), fully discharge then fully charge, then set the true value. GEN2: set in APP |
| 3 · Re-sync capacity | GEN1: after full discharge long-press [▼] to 0%, or after full charge long-press [▲] to 100% — no repetition needed. GEN2: set 100% after full charge or 0% after full discharge |
| 4 · Factory reset | GEN1: [▼]+[▲] together 5 s. GEN2: rear Reset key 5 s. Not needed in normal use |
Share your battery capacity and maximum main-circuit current — we'll configure the CAP preset and shunt range before shipment. Batch vehicle programs can be pre-configured at the factory.
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