Blue Sea M2 OLED DC Voltage Monitor for Four Battery Banks
Blue Sea M2 OLED DC Voltage Monitor for Four Battery Banks
Auto-Dimming Display, 80dB Alarm & Isolated MOSFET Relay

DESCRIPTION
Comprehensive Multi-Bank DC Voltage Tracking for Marine and Off-Grid Systems
Managing complex electrical systems in marine vessels, caravans, and off-grid installations requires precise, real-time data. The Blue Sea M2 OLED DC Voltage Monitor provides a centralised solution for tracking up to four independent battery banks from a single, compact gauge. By consolidating multiple readouts into one unit, this digital voltmeter eliminates dashboard clutter and simplifies the installation process compared to fitting individual gauges for your starter, house, thruster, and auxiliary batteries.
Superior Visibility with Auto-Dimming OLED Technology
Standard LCD screens often suffer from poor viewing angles, washout in direct sunlight, or excessive glare during night navigation. The M2 series addresses these challenges by utilising a high-contrast OLED digital display. This screen delivers sharp, crisp characters that remain easily legible across a wide viewing angle, even in bright marine cockpits or sunlit vehicle cabins.
To preserve night vision during evening operations or while sleeping in a camper, the integrated light sensor automatically dims the display brightness based on ambient lighting conditions. Tactile front-panel buttons allow for effortless navigation and programming across all four monitored channels, even when operating in rough seas or travelling over corrugated tracks.
Proactive Battery Protection and Alarm Integration
Relying solely on manual visual checks can lead to missed over-discharge events or charging system failures, which can permanently damage expensive deep-cycle batteries. This multi-bank battery monitor mitigates that risk through proactive, automated alerting. Users can configure custom high and low voltage thresholds tailored to specific battery chemistries and system requirements.
- Multi-Bank Capability: Simultaneously tracks DC voltage across up to four separate battery banks from a single instrument.
- Daylight-Readable OLED Screen: High-contrast display with automatic dimming ensures optimal visibility in all lighting conditions without compromising night vision.
- Programmable 80dB Alarm: Integrated visual indicator and loud 80dB audible buzzer alert operators immediately to out-of-bounds voltage conditions.
- Isolated MOSFET Relay: Built-in relay output allows the monitor to trigger external indicators, loud sirens, or automated system responses when voltage thresholds are breached.
- Intuitive Tactile Controls: Front-mounted buttons provide straightforward setup, alarm muting, and seamless cycling between battery banks.
Advanced Automation via Isolated MOSFET Relay
Beyond its internal 80dB audible buzzer and visual warning indicator, the unit features an integrated isolated MOSFET relay. This critical feature elevates the unit from a passive display to an active system controller. When a low or high voltage threshold is triggered, the relay can be wired to activate external warning lights in a remote cabin, sound a high-output external horn in loud engine rooms, or interface with compatible battery management switches and generator start modules to protect your power reserves automatically.
Applications Across Marine, RV, and Commercial Fleets
Engineered for demanding environments, the Blue Sea Systems M2 monitor is suited for a wide range of multi-battery architectures, including:
- Marine Vessels: Monitor port and starboard engine start banks, house banks, and bow thruster or windlass batteries from the helm or navigation station.
- Caravans and Motorhomes: Keep track of the primary chassis battery alongside multiple auxiliary deep-cycle house banks.
- 4WD Dual and Triple Battery Setups: Ensure your cranking battery remains isolated and charged while drawing down auxiliary batteries for camping refrigeration and accessories.
- Emergency and Commercial Vehicles: Maintain strict oversight of critical communications and equipment power supplies.
Upgrade your electrical panel with the Blue Sea M2 OLED DC Voltage Monitor to safeguard your battery investments and maintain complete oversight of your onboard power systems.
SKU: BS-1833B
SPECIFICATIONS
| Specification | Details |
|---|---|
| Product type | DC voltage monitor |
| Display | Bright OLED display with auto-dimming |
| Battery banks monitored | Up to four |
| Alarm | Adjustable 80dB alarm |
| Relay | Isolated MOSFET relay |
| SKU: | BS-1833B |
| Model #: | BS-1833B |
| MPN: | BS-1833B |
| Package weight: | 0.216 kg |
| Package length: | 0.11 m |
| Package width: | 0.11 m |
| Package height: | 0.08 m |
WARRANTY
Blue Sea Warranty Policy
Blue Sea Systems products sold by us are supplied with a warranty against defects for the warranty period shown below, subject to the product type, application and the terms of this warranty policy.
The express warranty provided by us is limited to a maximum of 5 years from the original date of purchase, unless otherwise required under Australian Consumer Law.
Blue Sea Systems may offer longer manufacturer support on some products at their discretion
Warranty Lengths by Product Range
| Blue Sea Product Range | Warranty Length | Application / Notes |
|---|---|---|
| Most Blue Sea Systems Products | 5 years | Applies to most Blue Sea Systems products found to be defective in materials or manufacture. |
| P12 Battery Chargers | 5 years | Warranty period starts from the original date of purchase. |
| P12 Remote Displays | 5 years | Warranty period starts from the original date of purchase. |
| Digital Meters | 3 years | Warranty period starts from the original date of purchase. |
| Vessel System Monitors | 3 years | Warranty period starts from the original date of purchase. |
Warranty Assessment and Remedy
If a Blue Sea Systems product is found to be defective in materials or manufacture within the applicable warranty period, we will, at our discretion, arrange a repair, replacement, store credit or refund, depending on the nature of the fault and the requirements of Australian Consumer Law.
Products may need to be returned for assessment before a warranty claim can be approved. Where required, the product must be returned with dated proof of purchase and a clear description of the fault.
Labour costs for removing, replacing, reinstalling or diagnosing a product are not covered by this express warranty unless otherwise required under Australian Consumer Law.
Making a Warranty Claim
To make a warranty claim, please contact us with your dated proof of purchase, product details and a description of the fault.
The product may need to be returned for inspection before the claim can be assessed. If the product is confirmed to be faulty and covered by this warranty, we will advise the available remedy.
What This Warranty Does Not Cover
This warranty does not cover faults or damage caused by incorrect installation, incorrect application, misuse, abuse, neglect, unauthorised modification, accidental damage, normal wear and tear, environmental damage, or failure to use the product in accordance with the manufacturer's instructions.
- Incorrect installation or wiring
- Incorrect product selection or application
- Misuse, abuse or neglect
- Physical or accidental damage
- Water ingress or environmental damage outside the product's intended use
- Unauthorised modification or repair
- Normal wear and tear
- Labour costs for removal, replacement, reinstallation or diagnosis
- Freight, travel or call-out costs unless otherwise required by law
- Products not returned for assessment when reasonably required
Manufacturer Support
Blue Sea Systems may provide additional manufacturer support on some products beyond the warranty period listed above. Where available, we may assist customers in contacting the manufacturer, but any manufacturer support beyond the express warranty period is subject to the manufacturer's own terms and continued availability.
Australian Consumer Law
This warranty is in addition to other rights and remedies available at law. Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.

