Blue Sea 40-90Hz Digital AC Frequency Meter
Blue Sea 40-90Hz Digital AC Frequency Meter
Blue Sea 80-249V AC Input - Splashproof Dimmable LED - 2 Inch Mount

DESCRIPTION
Precision AC Frequency Monitoring for Marine and Off-Grid Power Systems
Maintaining stable alternating current frequency is critical when operating sensitive electronics, heavy-duty appliances, and electric motors in mobile, marine, or remote environments. This digital AC frequency meter by Blue Sea Systems provides accurate, real-time monitoring from 40Hz to 90Hz, allowing you to instantly verify the health and performance of your shore power, onboard generator, or inverter output. By continuously tracking frequency fluctuations, this gauge helps prevent premature equipment failure, overheating, and erratic appliance behaviour caused by unstable power sources.
Universal Voltage Compatibility for 120V and 240V Systems
Engineered for versatility, this digital meter accepts a wide input voltage range of 80V to 249V AC. This broad compatibility makes it suitable for both standard Australian 230V/240V 50Hz mains and off-grid grids, as well as international 110V/120V 60Hz marine and imported RV electrical architectures. Whether you are cruising internationally on a vessel and connecting to varied dockside shore power, or managing a diesel generator in an off-grid cabin, this single unit adapts seamlessly to your AC bus without requiring external step-down transformers.
Key Features and Benefits
- Wide 40Hz to 90Hz Measurement Range: Accurately tracks standard 50Hz and 60Hz systems while providing ample headroom to diagnose severe generator governor droop or runaway conditions.
- Broad 80V to 249V AC Input: Operates directly across standard domestic, commercial, and international AC voltage networks.
- Splashproof Front Face: Built to withstand damp marine environments, cockpit dash panels, and exposed caravan electrical lockers.
- Adjustable 3-Level LED Display: The bright red three-digit readout features integrated dimming controls to ensure clear visibility in direct sunlight without causing night-blindness in dark cabins or wheelhouses.
- Manual Sleep Mode: Easily blank the display when the system is not in active use, reducing parasitic power draw to preserve your auxiliary energy reserves.
- Simple Threaded Panel Mount: Designed to fit standard 2-inch (approx. 51mm) gauge cut-outs, secured from the rear with a large, hand-tightened locking nut for rapid installation without complex mounting brackets.
Why Upgrade from Standard Analogue Gauges?
Traditional mechanical reed or pointer frequency meters can suffer from vibration fatigue, sticking needles, and poor resolution, making it difficult to spot minor frequency drift before it damages your air conditioning compressors or battery chargers. This solid-state digital AC frequency meter eliminates moving parts, offering reliable shock resistance in rough seas or corrugated outback tracks. The crisp 0.5625-inch (approx. 14.29mm) LED characters provide an unmistakable readout at a glance, removing the guesswork of interpreting analogue scales.
Ideal Applications
- Marine Vessels: Monitor gensets, shore power isolation transformers, and marine inverters at the main AC switchboard.
- Caravans, Motorhomes, and RVs: Verify the stability of portable petrol generators or camp-ground hook-ups before engaging sensitive roof-top air conditioners.
- Off-Grid Solar and Hybrid Systems: Keep a dedicated eye on stand-alone inverter frequency regulation and backup generator synchronization.
- Mobile Service Trucks and Workshops: Ensure mobile power take-off (PTO) generators are spinning at the correct RPM to deliver clean power for industrial tools.
Protect Your AC Electrical System
Equip your main switchboard or control panel with reliable, commercial-grade instrumentation. Integrate this Blue Sea digital AC frequency meter into your electrical setup today to safeguard your onboard appliances and ensure consistent power quality wherever you operate.
SKU: BS-8239B
SPECIFICATIONS
Specifications
| Manufacturer Part Number | 8239 |
|---|---|
| Meter | Frequency |
| Function | 40 to 90 Hz |
| Input Voltage | 80-249 V |
| Display Character Size | 0.5625 in (14.29 mm) |
| Display Brightness | 3 levels |
| Front | Splashproof |
| Maximum Power Consumption | 1 W |
| Sleep Mode | Manual |
| Weight | 0.72 lb (0.33 kg) |
| SKU: | BS-8239B |
| Package weight: | 0.396 kg |
| Package length: | 0.11 m |
| Package width: | 0.09 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.







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