Transmission types All All All V2512AT only
Features
Basic shift strategy x Enhanced shift
strategy -
(GCW up to 60t) x x x
Heavy GCW control
(GCW 61-130t) x
Gearbox oil temp.
monitor x x x x
Basic Distribution Long haul Heavy
& construction Fuel & Haulage Economy
TP-BAS TP-DICON TP-FUEC TP-HEAVY
Transmission types All All All V2512AT only
Features Smart cruise
control x x
Performance shift x x x x
Options (Extra cost) Gear selection
adjustment in automatic
+ kick-down x x x
Enhanced PTO
172 I - Shift - Gen. C
Package
description TP-BAS - The standard supplied package providing the basic I-Shift functions.
TP-DICON - Incorporates features to suit distribution and construction work. Includes e.g. - features to aid manoeuvrability in confined spaces, and when starting off from standstill.
TP-FUEC - Incorporates features to minimise fuel consumption - particularly suitable for long haul work.
TP-HD - Includes features to optimise performance with heavy GCW - >60 tonne.
Feature descriptions
Basic Shift Strategy - Automatic selection of the correct starting gear (1st. - 6th. gear) to take account of gross vehicle weight and road gradient.
Enhanced Shift Strategy* - I-Shift interacts with ECS and EBS to aid manoeuvrability in confined spaces, and when starting off from standstill.
Shifts during engine braking are made smoother by applying the wheel brakes, to increase braking power.
Heavy GCW Control** - Optimises gear shifts for GCW 60 - 180 tonne operation.
EcoRoll - Reduced fuel consumption by automatic activation and deactivation of free-wheel function when neither engine power nor braking is needed
- e.g. on level roads.
* EBS-MED/
EBS-HIG required
** Available only with certain engine/
transmission combinations
174 I - Shift - Gen. C
Feature
descriptions Launch Control*** - I-Shift interacts with EBS to optimise gear selection when manoeuvring at low speed.
Also includes enhanced hill start control.
Basic Gear Selection Adjustment - allows gear selection using the +/- buttons on the gear selector lever, during engine braking in automatic mode.
Gearbox Oil Temperature Monitor - temperature shown on display.
Smart Cruise Control - I-Shift interacts with EBS to ensure that auxiliary brakes are not applied unnecessarily, allowing more frequent activation of Eco-Roll.
*** EBS and ECS required
Performance Shift - by intelligent control of the engine compression brake - VCB/VEB - countershaft brake, and clutch, gear shifts can be made faster and smoother.
Enhanced PTO functions - includes features to make PTO operation easier - e.g. limitation of engine speed.
Enhanced Gear Selection Adjustment - allows gear selection using the +/- buttons on the gear selector lever, when starting off and driving in automatic mode.
Also includes a ʻkick-downʼ function. Pressing accelerator pedal right down causes down-shift for - e.g. overtaking.
Option descriptions
Feature descriptions
176
Powertronic
178
Powertronic
General
information The Powertronic transmission was originally fitted to dumper trucks manufactured by the construction equipment division of Volvo Corporation.
The transmission was first introduced by Volvo Truck in 1996, and fitted to FL10 trucks for use as refuse collection vehicles. These were mainly 8x4 vehicles.
Volvo
Transmission
16 (17) (19) (22) Nm - max. input torque 05 (06) forward gears
PT Powertronic Designations
180
Powertronic
Generations Since first being introduced, the Powertronic transmission has evolved through four generations. The significant features are:
Gen.1 - One fluid filter. Two connectors on ECU (FL10, FL12)
Gen. 2 - Two fluid filters. Turbine speed sensor. S13 solenoid, Pulse Width Modulated (PWM) signal for brake pressure. Three connectors on ECU (FL10, FL12)
Gen. 3 - Truck Electronic Architecture (TEA). Transmission Electronic Control Unit (TECU). Transmission Electronic Control Unit (TECU). Gear Selector Electronic Control Unit (GECU). S14 PWM signal for lock-up pressure (FM)
Gen.4 - I-Shift type selector lever. PWM valve and pressure
182 Powertronic
A B C D E
K1 K2 B1 B2 B3 B4 B5
Construction Powertronic is a fully automatic transmission, using planetary gearsets and a torque convertor.
The main sections of the transmission are:
A. Torque convertor B. Fluid pump
C. Retarder (Optional)
D. Forward and reverse clutch E. Planetary gearsets
K1 and K2 are multi-plate clutches.
B1 - B5 are multi-plate brakes.
These are used to lock components of the gearsets in various combinations to obtain the available gear ratios.
184 Powertronic
3
4
2 1
5 6
Torque convertor - main components
A torque convertor is a special type of fluid coupling, which has the ability to multiply torque from the engine.
It takes the place of the clutch used with a manual gearbox.
The main components are:
1. Impeller - or pump - wheel, which is attached to the engine flywheel and is, therefore, the input member.
2. Turbine wheel, which is attached to the turbine shaft (3) and is, therefore, the output member.
4. Stator, which is attached to the transmission casing via a one-way clutch.
The clutch prevents the stator spinning with the fluid - it can spin only in the opposite direction.
On the inner faces of impeller (1) and turbine (2) are formed several radial vanes.
The stator (4) also has a series of vanes.
Impeller Turbine Stator
186 Powertronic
2 4 1
When the engine is running, the space between these three components is filled with fluid.
When the impeller (1) is rotating and, because of the special shape of the impeller and turbine vanes, a circulation of fluid is created. The impeller imparts a force to the fluid, which is thrown from the impeller vanes onto the turbine vanes. The force is applied to the turbine vanes, and the turbine (2) also starts to rotate.
As the impeller speeds up, so does the turbine.
However, fluid leaving the turbine still has some residual force. Again, due to the relative rotation and shape of the vanes, fluid is directed against the stator vanes (4).
Because the one-way clutch locks the stator against the direction of fluid impact, the fluid is forced to change direction.
Torque convertor - operation Fluid circulation
and force
Residual force
188 Powertronic
3
4
2 1
5 6
Torque convertor - operation
The stator vanes throw the fluid back onto the impeller vanes, in a direction which aids rotation.
The residual force of the circulating fluid is added to the torque provided by the engine - hence the termʼ torque convertorʼ.
Torque multiplication is highest - typically 2:1 - when the impeller speed is high, and the turbine speed is low.
Eventually, the turbine speed approaches that of the impeller.
However, because of circulation losses, the speeds can never actually match 100%. There will always be some ʻslipʼ meaning that the turbine rotates slightly slower than the impeller.
This slip is a loss of efficiency, which has a bearing on performance and fuel economy.
To eliminate slip, once the relative speeds of the impeller and turbine reach a certain point, lock-up clutch (5) is engaged.
For more information, see Lock-up clutch.
Efficiency loss
190 Powertronic
The pure hydraulic coupling of engine to transmission, before the lock-up clutch is engaged, gives a fluid coupling a valuable characteristic - the ability to transfer torque from the engine to the transmission very smoothly.
Unlike a conventional clutch, a fluid coupling suffers virtually no wear. This is the reason that, in conjunction with an automatic transmission, these couplings are ideal for use in ʻstop/startʼ conditions - e.g. buses and refuse collection vehicles.
However, hydraulic coupling does have a slight drawback.
Because torque is being transferred all the time the engine is running - even when it is idling - there is always a slight tendency for the vehicle to creep slowly forwards.
Unless there is an automatic feature in the brake system to counteract this tendency, the vehicle must be held stationary by applying the foot brake or park brake.
Smooth torque transmission
No wear
Torque drag
192 Powertronic
1 2
4 3
PTO and fluid
pump drive The PTO drive gear (1) is driven from intermediate gear (2).
The transmission fluid pump (3) is driven from drive sleeve (4).
194 Powertronic
K1 K2 B1
B2 B3 B4 B5
1 2
3
Clutches and brakes
The available gear ratios are obtained using multi-plate clutches (K1 and K2) and brakes
(B1 - B5). The number of brakes depends on the number of gear ratios available in the transmission.
The clutch and brake packs consist of interleaved metal plates and friction plates.
The clutch or brake is applied by hydraulic pressure acting on a piston.
When applied, clutch (K1) connects turbine shaft (1) to mainshaft (2). Clutch (K2) connects turbine shaft (1) to tubular shaft (3).
Brakes (B1 - B5) lock either the planetary gears, the gear carrier, or the sun gear to the transmission housing in various combinations to provide the available gear ratios.