Kerbdog:
Lets disect this load of ■■■■■■■■ shall we?
Most of the time the ‘red’ or ‘parking’ button is redundant now as trailer brakes lock on once the emergency sussie is disconnected.Trucks are required to have a mechanical system to apply brakes in case of loss of air pressure, it is air pressure that releases spring brakes
Very rarely is there any air left to use a shunt button if a trailer has been left standing, plus they also seize up because they are hardly ever used.More the reason to use them and defect the air leak on your circle checks
Some ‘black’ buttons lift up an axle on the trailer or even are used to slide a trailer (skelly) used for containers to a smaller size.In case of confusion. RTFM
The most important thing though is this… There is a notice on a board where I go in which it outlines the dangers of not pulling the parking brake first before disconnecting the emergency sussie.
Pulling off the red line does not put on parking brakes, nor does coupling the emergency line release parking brakes.
A lot of trailers that are used in Europe do not lock the brakes on when the sussie is pulled
EC 71/321-98/12 The parking braking system shall enable the vehicle to be held stationary on an up or down gradient even
in the absence of the driver, the working parts being then held in the locked position by a purely mechanical device.
(different couplings too for European trailers (Palm couplings which are basically rubbish !!)).
Palm Couplings or Glad Hands are used in every other EU and American State. When fitted and maintained correctly they are better than C Type
Also if they are very closely coupled it can be awkward to get behind the truck and between the trailer to disconnect the sussies,
stop-gapcoupling.com/Docs/sp … edures.pdf
some drivers pull the unit out like this one guy did, needless to say, he didn’t apply the parking brake, then pulled the air lines and the trailer rolled forward and jumped the fifth wheel killing him.
Check Trailer height against pin, raising or lowering suspension or landing legs.
So really, it’s always a safe to pull the brake first no matter what,
hse.gov.uk/workplacetranspor … upling.htm
shunters will just have to get used to it, but at least you wont kill anyone.
But they might!
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