For the trucking industry, adopting technology to be smarter involves some smart trucks, smart braking systems, telematics, alongside some, seemingly, not so smart compliance requirements!
We need to be smarter and start using the basics of these smart technologies for simpler, smarter compliance outcomes, says Bob Woodward, Australian Trucking Association Chief Engineer.
It is disappointing how the mandating of some safety technologies is accepted as a ‘well I have to do it’, as long as it’s fitted, from there I really don’t care! EBS is more, much more than that, and as with many technologies, we don’t know what we don’t know.
However, we also need to be willing to have our ‘what we don’t know’ horizons expanded and start to embrace, by learning and implementing, being more receptive and delving more into the unknown, to start asking the questions, what’s in it for me?
Recently, an operator called to enquire about a statement that he had heard operators can extract axle group weights from a Trailer-EBS system. In respect of trailers, the answer is a definite yes, but may not be so readily accessible, if you don’t have the appropriate outputs/displays.
The fact of the matter is ,you can, and by managing some other specific factors the results can be surprisingly accurate. My own experience, has seen triaxle weights within 80 kg of the certified weigh-bridge are consistently achievable.
But the T-EBS system must be appropriately powered, the suspension needs to be correctly setup and the systems configured and calibrated. The suspension must be set at operating ride-height and the suspension eye bushes must only be torqued up when the suspension is at ride height with the brakes released (many aren’t).
Then the T-EBS system lower and upper calibration set points must be configured using actual weigh-bridge masses (with all brakes released). The ATA-ITC produced a Technical Bulletin with input from ITC partners BPW Transpec, Fuwa K-Hitch, Hendrickson, MaxiTrans and SAF Holland (each ITC members) to assist operators. (See QR Code at the foot of this article.)
The fact is, the T-EBS smarts and mass basics are what provides the inputs for electronic brake load proportioning. So, it’s time to refocus and keep compliance requirements simple. Remember, when using suspension-based technologies for mass management, the vehicle needs to be on level ground and the brakes released to get superior results.
With a few basics sorted, is a fully functioning trailer T-EBS smart? Definitely! So, what could go wrong? Plenty, some of the systems supporting EBS leave much to be desired.
The Australian Design Rules ‘Definitions and Categories’ states:
B-Double, a combination of vehicles consisting of a prime mover towing two ‘Semi-trailers’.
Road Train, a combination of vehicles, other than a ‘B-Double’, consisting of a motor vehicle towing at least two trailers (counting as one trailer a ‘Converter Dolly’ supporting a ‘Semi-trailer’).
ADR 35/06 Clause 5.8.2 says, ‘Each vehicle designed to be used in ‘Road Train’ combinations, must be equipped with a special connector conforming to ISO 7638-1:2003, together with a permanent electrical supply system configured for 24-volt operation.
Note 3 adds, ‘This does not prevent fitment of an additional ISO 7638-2 connector for a 12-volt nominal supply voltage.’
Sounds simple enough, but there are suppliers and operators who don’t seem to (or want to) understand the downsides, a 12-volt supply just doesn’t cut it as an EBS power supply when there are more than two trailers and if you count the converter dolly as a trailer, an A-double has three trailers.
The downsides of reduced voltage (brown-out) can impact negatively. You can get an over-braked dolly, impacting on safety, or the rear trailer wheels lock-up when lightly laden, plus, there’s trailer swing. Whether you call it a road train or a PBS A-double or a B-triple or any other combination, if it isn’t a B-double and has two or more trailers, it’s a road train and the Trailer EBS supply needs to be 24-volt.
So, what can go wrong with an EBS brown-out? Lots, including over-braking and loss of EBS functions on the trailing trailer/s.
Click here for the relevant ATA Technical Bulletin
IF IN DOUBT. Talk to your relevant T-EBS supplier: HALDEX, Knorr Bremse or WABCO.
