FEATURE HIGHLIGHTS
Core Capabilities
OBDResource BM550U Battery Tester with Built-In Printer
Product Overview
Test, understand, and document battery condition with one compact tool. The OBDResource BM550U is a digital automotive battery analyzer designed for compatible 6V, 12V, and 24V lead-acid batteries rated from 100 to 2000 CCA.
The BM550U measures battery voltage, State of Health (SOH), State of Charge (SOC), available CCA, and internal resistance. Results are shown clearly on the 1.8-inch color display, while the built-in thermal printer produces a paper report for customers, maintenance records, or before-and-after comparisons. It also supports AH-to-CCA conversion and real-time voltage waveform monitoring.
Key Features
- Built-In Thermal Printer – Print battery test results directly from the tester for convenient record keeping and customer reports.
- 6V, 12V & 24V Battery Testing – One tester covers a wide range of passenger, powersport, marine, RV, and commercial vehicle batteries.
- 100–2000 CCA Test Range – Suitable for testing compatible batteries from smaller starting applications to larger truck and equipment batteries.
- Complete Battery Health Data – View voltage, SOH, SOC, measured CCA, rated CCA, internal resistance, and an overall battery condition result.
- AH-to-CCA Conversion – Enter a known capacity from 2Ah to 220Ah to obtain the corresponding CCA reference without checking a separate conversion chart.
- Voltage Waveform Monitoring – Observe voltage changes visually and review minimum, maximum, and current voltage values on the screen.
- 1.8-Inch Color Display – Clear menus and easy-to-read results support fast testing in the garage, workshop, or field.
- In-Vehicle or Off-Vehicle Testing – Test a compatible battery while installed in the vehicle or after it has been removed.
- Heat- and Cold-Resistant Design – Designed for use in working environments from −20°C to 50°C (−4°F to 122°F).
Applications
- Checking battery health before seasonal storage or a long trip
- Identifying weak, discharged, or aging batteries before replacement
- Printing test reports for repair-shop customers and service records
- Evaluating battery condition during vehicle inspections and routine maintenance
- Comparing battery readings before and after charging or service
- Testing batteries for cars, pickup trucks, SUVs, motorcycles, ATVs, RVs, boats, trucks, golf carts, and lawn equipment
- Use by vehicle owners, repair shops, battery distributors, and battery service professionals
Compatibility
The BM550U is compatible with 6V, 12V, and 24V lead-acid batteries rated from 100 to 2000 CCA. Supported battery constructions include:
- Conventional flooded lead-acid batteries
- AGM flat-plate batteries
- AGM spiral-wound batteries
- GEL batteries
It can be used with compatible batteries installed in cars, motorcycles, ATVs, SUVs, pickup trucks, commercial trucks, RVs, boats, golf carts, and lawn mowers. Always select the battery’s actual voltage, type, and rating shown on its label before testing.
Not intended for lithium batteries. Vehicle type alone does not determine compatibility; the installed battery must fall within the supported voltage, chemistry, and rating range.
How to Use
- Check the battery label. Confirm the battery voltage, construction type, and rated CCA before beginning the test.
- Connect the clamps. Attach the red clamp to the positive (+) terminal and the black clamp to the negative (−) terminal. Make sure both clamps contact clean metal securely.
- Select Battery Test. Choose 6V, 12V, or 24V, then select the correct battery type and enter the rating shown on the battery label.
- Review the results. Read voltage, SOH, SOC, CCA, internal resistance, and the overall condition displayed on the color screen.
- Print the report. Use the built-in thermal printer to create a physical copy of the test results when needed.
- Use additional functions as required. Select CCA/AH conversion when only an AH value is available, or open Waveform Monitoring to observe voltage changes over time.
Technical Specifications
| Brand | OBDResource |
|---|---|
| Model | BM550U |
| Product Type | Digital automotive battery analyzer with thermal printer |
| Supported Battery Voltages | 6V / 12V / 24V |
| Battery Rating Range | 100–2000 CCA |
| Supported Battery Types | Flooded lead-acid, AGM flat plate, AGM spiral, GEL |
| Battery Test Data | Voltage, SOH, SOC, measured CCA, rated CCA, internal resistance, overall condition |
| AH-to-CCA Input Range | 2Ah–220Ah |
| Waveform Function | Real-time voltage waveform with current, minimum, and maximum voltage reference |
| Display | 1.8-inch color LCD |
| Printer | Built-in thermal printer |
| Testing Location | In-vehicle and off-vehicle |
| Working Temperature | −20°C to 50°C / −4°F to 122°F |
What’s in the Box
- 1 × OBDResource BM550U Battery Tester with built-in thermal printer
- 1 × Integrated test cable with red and black battery clamps
- 2 × Thermal paper roll
- 1 × Quick Start Guide
- 1 × User manual
Package contents may vary by production batch. Please refer to the package received for the final contents.
Important Notes
- Use only on supported 6V, 12V, or 24V lead-acid batteries within the 100–2000 CCA range.
- This tester is not designed for lithium-ion, LiFePO4, or other lithium battery chemistries.
- Enter the battery rating printed on the battery label. An incorrect voltage, battery type, or rating can produce misleading results.
- Clean corroded or dirty terminals and ensure solid clamp contact before testing.
- The AH-to-CCA result is a conversion reference. Battery design and manufacturer specifications can affect the relationship between AH and CCA.
- The voltage waveform provides a visual reference for voltage changes; it is not a full laboratory oscilloscope or a substitute for complete charging-system diagnosis.
- Battery condition should be evaluated together with symptoms, battery age, charge level, and the vehicle manufacturer’s service information.
FAQ
Can the BM550U test 6V, 12V, and 24V batteries?
Yes. Select the correct voltage before testing and confirm that the battery is a supported lead-acid type rated within 100–2000 CCA.
Which battery types are supported?
The BM550U supports conventional flooded lead-acid, AGM flat-plate, AGM spiral-wound, and GEL batteries. It is not intended for lithium batteries.
What information appears in the battery test?
The tester displays voltage, State of Health, State of Charge, measured CCA, rated CCA, internal resistance, and an overall battery condition result.
Can I print the results immediately?
Yes. The built-in thermal printer lets you print a test report directly from the BM550U without connecting it to a separate printer.
Can the battery be tested while it is still installed?
Yes. The BM550U supports both in-vehicle and off-vehicle battery testing. Turn off vehicle accessories and follow the operating instructions before testing.
What does the AH-to-CCA function do?
Enter a known capacity between 2Ah and 220Ah to obtain a corresponding CCA reference. Because AH and CCA measure different battery characteristics, use the battery manufacturer’s stated CCA whenever it is available.
Does waveform monitoring test the alternator?
It displays battery voltage changes as a waveform and shows current, minimum, and maximum voltage values. These readings can provide a useful visual reference, but they do not replace a complete starting and charging system test.
Does the tester require separate batteries?
No separate household batteries are required during normal use; the tester is powered through its connection to the battery being tested.
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Compare Models
Compare the specifications that matter for your application.
| Comparison | Current ModelBM550U $59.99 USD | BM550 $25.99 USD | BM520 $79.00 USD |
|---|---|---|---|
| Voltage | 6V / 12V / 24V | 6V / 12V / 24V | 6V / 12V / 24V |
| CCA Range | 100-2000 CCA | 100-2000 CCA | 100-2000 CCA |
| Battery Types | Regular Flooded, AGM Flat Plate, AGM Spiral, GEL, and EFB | Regular Flooded, AGM Flat Plate, AGM Spiral, GEL, and EFB | Regular Flooded, AGM Flat Plate, AGM Spiral, GEL, and EFB |
| System Tests | SOC/ SOH/ Voltage/ Resistance /Waveform Monitoring | SOC/ SOH/ Voltage/ Resistance | SOC/ SOH/ Voltage/ Resistance/ Loading Test/ Crank Test/ Loading Test/ Waveform Monitoring/ Data Review/ |
| Display | 1.8-in HD color display | 1.8-in HD display | 2.4-in HD color display |
| Key Capability | Built-in thermal printer | Three-Step Test Result | Live waveform and non-polarity connection |
Swipe to compare models
Battery testers are expensive, especially ones with a printer. I gave this one a shot because I have several batteries to keep track of and wanted to see when they need replaced or trickle charged. The first battery I check is a brand new marine battery. As expected it tested at 99%. The second the battery in my truck that’s only a few months old. It tested at 98%. The third was a dual battery setup in my diesel truck. These batteries are pretty old and don’t hold a charged for very long. The test was 16% but it said the voltage was 12.7v. It also said the voltage for the other batteries was 12.7v which seems odd that all 4 read the same voltage. Unfortunately I don’t have a name brand battery tester to compare it to but I would say it seems to be accurate enough based on what I expected the results to be. It does tell you what the state of charge and health is too. The other option is waveform and voltage. The manual doesn’t mention anything about this option. I’m assuming this is used to see if the alternator is working correctly because if your battery voltage has a waveform you better run. All and all I think this is a good buy if you have multiple batteries to maintain or if you want something cheap for a auto shop and want to print the results for a custom.
This is an inexpensive and easy way to test a battery without stressing it like a load tester does. Wo0rks great and prints the results for you if wanted.
At first, the printer part would not print normally. I did three prints, and it came out so small I couldn't read any of them. I was about to return it, then I opened and closed the printer paper door, even though everything already looked normal. I printed again for a 4th time, and then the print was normal (See picture). I'm not sure what was going on, and hopefully it won't do it again. You can see the results without printing, even though you have to select ok to print before you can see the information. I wish the screen were slightly bigger so they wouldn't have to abbreviate everything.It also lets you view a line graph of the voltage, which is kind of neat.The printer function is kind of a novelty and only useful if you do automotive services, but for the price, this seems like a good deal if it continues to work fine.
Arrived as pictured. Shipping was fast. easy to use and worked perfectly. Great readable battery info and I made points with my husband. ( bonus ) He tossed his old one right away. Give yourself an upgrade - glad we did. Several languages to! Worth the cost-
This was my first time using a battery tester like this, and I was impressed with how simple it was. I usually have to go to the auto parts store when I think a battery may be going bad, so it was nice being able to check it myself at home. I like that this tester powers up from the battery, so there is no need for its own internal power source. The menu was clear, easy to read, and very easy to figure out.Testing the battery was quick and intuitive. It lets you run a battery test and also check the voltage waveform. For the battery test, I had to enter the CCA rating, and thankfully that number was printed right on my battery. The test finished fast, and I was able to print the results using the included paper. The only issue I had was that the paper did not always feed through smoothly unless I helped pull it a little while it was printing. Aside from that, this is a very useful device and a great one to keep around.
I did a shoot out and compared this to a battery tester that costs 10x the price and it gave me the same exact readings. It has nearly all the same functionality and I love that they include the printer so you can go back and referenctest.This thing is built really well. It’s made of sturdy plastic and the screen is really easy to read. You have to open the door to the thermal printer and pull the paper out a little bit before using or the paper will jam. If you’ve used a modern point of sale system or receipt printer it works exactly the same.This thing is a screaming good deal. If you work with batteries regularly, it’s a no-brainer and a must buy. You’ll be very pleased with it. Why pay 10x more for something that gives you identical readings when you can order this one. A+
Ich habe das Gerät hauptsächlich aufgrund der kompakten Größe und der integrierten Druckfunktion gekauft.Es misst zuverlässig die „Batteriegesundheit“ und erkennt defekte Batterien. Eine direkte Generatorprüffunktion ist zwar nicht vorhanden, jedoch lässt sich über die Spannungsaufzeichnungsfunktion problemlos die Ladespannung sowie der Spannungsabfall beim Starten des Fahrzeugs messen.Zum Vergleich habe ich die Messwerte mit einem deutlich teureren Gerät, dem Bosch BAT 131, verglichen, das etwa das 30-Fache kostet. Die Ergebnisse können sich absolut sehen lassen.Bei mehreren Messungen gab es leichte Abweichungen, allerdings bei beiden Geräten. Beim günstigeren Gerät fielen die Differenzen etwas größer aus. Das könnte unter anderem daran liegen, dass die Klemmen unterschiedlich saßen oder die Batterie noch im Fahrzeug verbaut war, worauf dieses Gerät möglicherweise empfindlicher reagiert.Für den Preis ist das Gerät vollkommen in Ordnung. Mit den Messergebnissen kann man gut arbeiten, besonders im Hobby- oder semiprofessionellen Bereich.
This little battery tester works great and is super easy to use. It comes preloaded with paper to print your test results and also includes one extra roll. I hooked this up to an 11 year old battery that is still being used in my second car, knowing it has to be very near the end of its very impressive life, and the tester reported that it was indeed in poor condition. To make sure the tester didn't work like a magic 8 ball and give random results, I tested the same battery again with the car running which I knew should give a super high reading, and that's exactly what it reported, as you can see from my pics of both tests. Also, the clamps are well built and hold firmly once connected to the battery terminals, and the screen (and print-outs) are easy to read. I recommend this battery tester for anyone who owns a car, as testing a battery yearly is a great way to get a jump on things while never needing one (pun intended!). As a side note, I did plan to replace my 11 yo battery but now I need to know just how long it will last so keep your eye out for a Guiness Book entry. In any case, I absolutely recommend this tester as a great value for the money!
In the old days the battery testers used to have a big resistor (like a heater coil) that tested the battery by putting a load on it and measuring the voltage drop, a simple analog meter showed good or bad. Well, this is the electronic version of the old ones, basically you set the parameters of your battery (voltage, capacity and expected cranking amps) and the tester do the calculations on how good the battery is, it only works with Lead Acid type, I tested on the pictures with a LiPo lithium and the results were completely wrong but is expected if the tester is calibrated for another type of chemistry. The best of this tester is the simplicity to operate it, and the fact it gives a bunch of info besides the good or bad message. The printer is a nice touch, maybe oriented for a business, it doesn't really matter for private use but is there and is included on the price which by the way is really good.
This little device will tell you if your car or small engine battery should be recharged or replaced. It will save you money and annoyance by helping you be informed as to the condition of your battery. It can keep you from being broke down due to a dead battery, and it can tell you when your battery just needs to be recharged, preventing unnecessarily buying a new battery.
For just a battery tester, it’s pretty decent. I have this as a spare for home only.
4 stelle perché non si può cambiare da cca in en
Comodo e pratico
IL PRODOTTO NON Può ESSERE ASCRITTO ALLA CATEGORIA DEI BENI PROFESSIONALI. TUTTAVIA LA MISURAZIONE RISULTA ATTENDIBILE E UTILE SE IL FINE SARA' QUELLO TI TENERE SOTTO CONTROLLO LA CARICA DELLA BATTERIA DELLA PROPRIA AUTO.
Der Autobatterietester ist klein und kompakt und funktioniert wie er sollte. Es sind keine Mängel zu finden und die Bedienung ist einfach
Bom
easy to use
Very accurate
Works well
Semplice da usare e fa quello che serve ad un prezzo dignitoso
Il prodotto è molto leggero e di qualità approssimativa. Quello che non capisco sono i valori che cambiano se si esegue più di una scansione consecutiva della stessa batteria. La prima analisi fornisce dei dati mentre le successive sono diverse. L’unico dato che rimane costante è la carica mentre la vita, la resistenza, il voltaggio e la cca variano. Sicuramente da un idea approssimativa dello stato della batteria ma non è molto preciso
Bought this so my wife could test her own battery if she was out or I was not around. This is simple to use and gives surprisingly accurate as tested against a know good multi-meter, and it provides useful information. Great price point for a well made and accurate instrument. Would buy again and Recommend.
This is a nice, easy to use, battery tester. It is so easy to use that you really don't need any instructions. Just choose Battery Test or Waveform option, then Cold Cranking Amps (CCA) or Amp Hours (AH), enter the appropriate value, with the Up/Down arrows, and hit OK to run the test. It's that simple and quickly gives you the results. The Waveform option won't be used too often, but it can help you determine if your alternator/voltage regulator is OK. That's a nice little addition that most battery testers don't give you.
