Denmark Category C/E Heavy Trailer Theory Test flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Speed limit for lorry with trailer

In Denmark a lorry over 3.5 t towing a trailer is limited to 80 km/h on motorways and 70 km/h on rural roads unless a lower limit is signed. The general 130 km/h motorway limit does not apply.

Overtaking ban sign for lorries

A red-bordered circular sign showing a red lorry on the left and a black car on the right bans goods vehicles over 3.5 t from overtaking multi-track vehicles. The ban applies to the whole combination.

Warning triangle on motorway

Place the warning triangle at least 50 m behind the combination on a motorway, behind the crash barrier where possible. On other roads, place it far enough back for approaching traffic to stop in time.

Maximum combination length Denmark

A rigid lorry plus drawbar trailer may be up to 18.75 m long; a tractor unit plus semi-trailer may be up to 16.50 m. Maximum width is 2.55 m and maximum height 4.0 m.

Air line connection order

Connect the red supply line first, then the yellow brake line. On uncoupling, disconnect yellow first, then red, so the trailer brakes are not released while the lines are still connected.

Trailer off-tracking in turns

A long combination's trailer tracks inside the tractor's path in a turn and the rear overhang swings outward. Allow extra lateral space and watch the trailer's rear wheels in the mirrors throughout the manoeuvre.

Correcting trailer snaking

Release the accelerator and, if fitted, apply the trailer brake lever gently. Never brake hard or steer sharply, because those inputs amplify the swing and can lead to a jack-knife.

Descending a long hill laden

Select a gear that holds the speed and use the retarder or engine brake. Apply the service brake in short firm applications rather than continuously, to avoid brake fade and loss of control.

Following distance for heavy combination

Keep at least 3 seconds in dry conditions and 6 seconds or more in rain or on gravel. The air-brake response delay and the combination's mass make close following unrecoverable.

Friction securing formula

n = (c - μ) × m × g / (2 × μ × STF × sin α), with c the acceleration factor, μ friction, m load mass, g 9.81 m/s², STF pre-tension and α lashing angle. Anti-slip matting raises μ and cuts the number of lashings.

Lashing capacity versus pre-tension

Lashing capacity (LC) is the maximum force a strap may transmit. Pre-tension (STF) is what the tensioner applies, and only STF counts toward friction-based securing. A typical ratchet strap has LC 2,500 daN and STF 250-500 daN.

Load securing acceleration factors

EN 12195-1 assumes 0.8 g forward, 0.5 g rearward and 0.5 g sideways for road transport. The securing system, not the curtain-side, must resist those forces.

Air brake system pressure

A lorry air-brake system runs at about 8-8.5 bar. The low-pressure warning must sound before pressure falls below about 4.5-5 bar, and the spring brakes apply automatically when pressure is lost.

Trailer roll test

Pull gently forward at walking pace and apply the trailer brake lever. The combination must slow and the trailer brakes must hold, confirming the trailer's brakes work independently of the tractor.

Air brake leak test

With the system charged and the engine off, apply and hold the footbrake. A pressure drop of more than about 0.2-0.3 bar per minute indicates a leak that must be repaired before driving.

Daily driving limit

A driver may drive 9 hours per day, extendable to 10 hours twice in a week. The weekly limit is 56 hours and the two-week limit is 90 hours.

Split driving break rule

After 4.5 hours of driving, take a 45-minute break, which may be split into 15 minutes followed by 30 minutes. The 15-minute part must come first; 30 then 15 does not count.

Documents carried at roadside check

Carry the driving licence, driver qualification card, tachograph records for the current day and previous 28 days, and the transport document (CMR note or national waybill) for the load.

Cyclist inside a turning lorry

The trailer's rear wheels cut inside the cab's path. A cyclist on the inside of a left turn is in the crush zone even after the cab has passed, so check the near-side mirror and blind-spot mirror before turning.

Blind spot beside the trailer

A car beside the trailer is invisible from the cab. A mirror check plus a shoulder check before changing lanes is the only reliable detection; a blind-spot camera or sensor is an aid, not a substitute.

Tyre tread depth requirement

Lorries and trailers need at least 1.6 mm tread across the central three-quarters of the tyre. A cut to the cord or a bulge is a defect regardless of tread depth.

Wheel nut indicators

Check pointers on wheel nuts must all point the same way. A displaced indicator signals a loose nut, and the wheel must be checked before the vehicle moves.

Defect that grounds the vehicle

Any defect affecting brakes, steering, tyres, lights or the coupling means the vehicle must not be driven. The driver records the defect and informs the operator before the vehicle moves.

CPR compression rate and depth

For an adult, give 30 chest compressions at 100-120 per minute, 5-6 cm deep, then 2 rescue breaths. Continue until the ambulance arrives or the casualty breathes normally.

Recovery position

An unconscious but breathing casualty is placed on the side, head tilted back and mouth pointing down. Monitor breathing until help arrives; do not move a casualty unless there is fire or further collision risk.

Eco-driving with a laden combination

Anticipate traffic, use the retarder and engine braking, keep tyre pressures correct and avoid idling. A well-driven laden combination can use 10-15 % less fuel than an aggressively driven one.

Uncoupling a semi-trailer

Park on level ground, apply the parking brake, lower the trailer legs, disconnect the electrical cable, then the yellow brake line, then the red supply line, and finally release the fifth-wheel handle.

Articulation angle limit

A semi-trailer can usually articulate about 90 degrees before the cab and trailer touch. A tighter turn damages the cab, the trailer corner and the air lines.

Trailer spring brake chamber check

The spring brake chamber must have a free stroke within the manufacturer's limit. An over-stroked chamber means the brake is out of adjustment and the trailer may not hold.

Split daily rest

A daily rest may be taken in two parts: an uninterrupted 3 hours plus an uninterrupted 9 hours, totalling 12 hours, within the 24-hour period from the end of the previous daily or weekly rest.

Motorway lane discipline for lorries

A heavy combination keeps to the right-hand lane except when overtaking. A long overtake at 80 km/h against a 90 km/h limit takes a long time and blocks faster traffic.

Tyre burst at speed

Hold the wheel firmly, ease off the accelerator and steer straight before braking gently. Braking hard on the burst side pulls the vehicle toward that side and can cause a roll-over.