Smaug1

My Background: I'm a regulatory engineer (electronics background). I worked for UL for 21 years and now I work for Snap-on Tools, helping them get cordless tools certified. I looked into the standards for certification requirements.

I found that there are a LOT that goes into safety certifications on an eBike: Bike system, battery and charger are all separate. Tests they do on the bike:

• Input: make sure the input current drawn doesn't exceed ratings
• Temperature: make sure that component temperatures don't exceed their specs. (which is easy to do, if components are under-spec'd or under-cooled)
• Isolation Resistance: measure the resistance of electric insulation to make sure it's adequate
• Dielectric Strength: test the electrical insulation with a high voltage to make sure it's adequate; doesn't arc
• Humidity Conditioning: Same as Dielectric, but after a humidity soak. (humidity can penetrate certain materials and reduce the insulation properties)
• Abnormal Conditions:
  • Overcharging
  • Component Faults
  • Blocked Ventilation
  • Locked rotor: Lock the motor up and confirm no fire, explosion, concentration of flammable gas, etc.
  • Running Overload: gradually overload the motor and confirm no fire, etc.
  • Battery short circuit
  • Imbalanced charging: This is an important one. There are dozens of cells in the pack they go out of balance over time and then when the charger charges to the same pack voltage, it means that the other cells in the pack are overcharged as a result of the tired cells not reaching their full voltage.
  • Shock: (kind of an impact test)
  • Thermal cycling: Confirming nothing bad happens when the bike is moved from a cold environment and back
• Impact
• Mold Stress: Makes sure the molded parts don't distort and expose anything that should be enclosed under hot conditions
• Flexing: checking wire harnesses to make sure they're rugged & reliable
• Ingress protection (IP testing) for dust and moisture; make sure safety-critical electrical spacings aren't effected
• Vibration: Checking the effects of shipping. You'd be surprised how many components will shake off a board in this test. Usually big capacitors and inductors that aren't glued down
• Strain Relief: Check that if a cord or harness is pulled, it can protect the electrical connections from the strain
• Startup Assistance Mode: confirms max 6 kph (3.7 mph) in walk mode and that it self-cancels if the button is released

The battery cells have to be certified on their own. Then, they are certified in the pack and again in a certified bike.

The chargers have their own requirements.

This is a big expense, but they really do make the bikes safer.

I remember when cheap Chinese hoverboards were burning houses down. The US government approached UL and asked them to write a standard so they could require it. Now that eBikes/batteries are burning down shops in NYC, there is a standard for electrical systems for eBikes (UL 2849) as well as for the battery packs for use in light electric vehicles (UL 2271).

Rick_D

Very informative, thanks!

TmMc

I will attest to UL's thoroughness in developing their certifications. I worked as a construction document reviewer for a local agency. A bit of my job was to verify UL certifications for photovoltaic, storage and generating equipment.

If you want to verify an ebike's UL certification(s) look at its UL labelling. then look that up on UL's online directories.

veganbikes

Snap On you say...please send me a digital Torque wrench at your price I will send you the money ; )

Really great informative post as well but it was hard to get past the Snap-On part as I love me some Snap-On : )

Doc_Wui

Back before we had internet, I was put in charge of UL safety approvals for our company's product. Good thing I had experts in my group because I knew nothing, but I developed a great respect for the tests and standards.

Are UL 2849 and UL 2771 available to the casual viewer on the internet. I would expect that you have to buy the test standards.

Smaug1

They're not free unless you have an active file with them. You'd have to buy a copy or subscribe to their services. Then, if the standard is based on an international one, rather than a legacy UL standard, it's not even included in the subscription. (which is kind of a racket, IMO)

You might be able to find older versions of those standards, which will be mostly the same, in a web search

Snap-on subscribes to their services and those aren't based on international standards, so I can view the standards and answer your questions, probably.

Oh, I see you're pretty local to me, we can get together for a beer some time and talk about it. I'm just over The Cheddar Curtain in Kenosha. Drop me a line if interested.

Smaug1

As an employee, I get 50% off retail price, which is still too expensive for someone who doesn't use the tools every day. If they gave us a better deal, they would really have to watch out for employees reselling them on ebay and in pawn shops. (and we lose our job if we get caught doing that, so it's high stakes)

Looking at the prices, I think our torque wrenches are priced pretty fairly. They're not like a $300 1/4" socket set or anything. ;-)

veganbikes

50% off retail works for me. I promise I won't tell anyone. I haven't even heard of Snap-On or Bike Forums!

The digital torque wrenches aren't cheap but they are good high quality tools so yeah you get what you pay for. I love everything Snap-On I have which isn't a ton of stuff but all really high quality high performance tools that get the job done and look good doing it.

Rick_D

Can't find a UL label on my BMC, only a reference to EN ISO 4210, which covers bicycles of any kind, and a Class 3 28 mph label.

https://www.iso.org/obp/ui/en/#iso:s...:-1:ed-2:v1:en

Did you know there's a maximum saddle height? You do now.

The motor, battery, display may have their own labeling but I'm not spelunking to find out.