1. POWER TAKE OFF’s 5 5 Engine Dependent: 1. Engine mounted
2. Integrated in the clutch bell housing
Clutch Dependent:
3. Driven by the transmission
Transmission dependent
4. Driven by the Transfer Box
5. Split-Shaft Box 5 5

2. POWER TAKE OFF APPLICATIONS
1. Engine mounted
2. Integrated in the clutch bell housing
3. Driven by the transmission
4. Driven by the Transfer Box
5. Split-Shaft Box

3. TRANSMISSION DRIVEN PTO’s
Suitable for most applications
Easy, low-cost installation
Retrofit always possible
Side Mounted PTO
The PTO is driven by one gear
off the layshaft.
Suitable for regular or heavy duty
and intermittent operation.
Rear Mounted PTO
The PTO is direct driven
by the splines at the end of the
transmission’s layshaft or, alternatively, of an
extension or auxiliary shaft.
Suitable for heavy duty, continuous operation.

4. SELECTING THE PTO
The catalogue includes all necessary information for the correct Power Take Off selection for each different application.
Before consulting the catalogue the following preliminary information should be collected:
What is the make and model number of your transmission?
What type of equipment will your PTO be driving?
Your driven equipment requires what horsepower, what rpm and what rotation?
The information in the PTO Selection Catalogue include:
Transmission Make and Model
PTO mounting location
PTO rotation
Gear position
PTO speed
PTO output torque
Part numbers of stud kits, spacers, adapters

5. THE PTO SELECTION CATALOGUE

6. TRANSMISSION MAKE AND MODEL
Successful Power Take Off selection requires correct transmission identification.
Transmissions are identified by the manufacturer’s tag located in various positions, depending on the manufacturer and the specific transmission.
The tag usually shows the following data:
Manufacturer’s name
Transmission model
1st gear ratio.shown hereunder refers to an EATON transmission) (
The example shown hereunder refers to an EATON transmission)
EATON spec number
Customer spec number/description
Model number
Serial number
Date of manufacturing

7. PTO MOUNTING SIDE
Before selecting the PTO location the main technical specifications (speed and torque) of the available PTO’s in the different locations have to be evaluated.
In the case more PTO apertures are available the one offering the most convenient installation should be preferred.
More than one PTO apertures may be
used simultaneously. In this case the
maximum allowed power output off
the transmission should not be exceeded.
Our technical department should be contacted
when several PTO’s are operated
simultaneously
1 SUP Upper
2 INF Bottom
3 POS Rear
4 DX Right Hand
5 SIN Left Hand
6 ANT Front

8. TRANSMISSION INSTALLATION
VERTICAL INSTALLATION
HORIZONTAL INSTALLATION

9. PTO ROTATION It is a key factor for the correct
selection of pumps or other
mechanical devices that have to be
run with only one rotation sense.
The rotation you find in the
catalogue refers to the rear output,
i.e. with the PTO output shaft
pointing toward the rear of the truck.
The
rotation only refers to the front
output if for some technical reasons
the PTO is not provided with the rear
output.
A special remark is made in this case.
Attention!
The PTO rotation is defined by looking at the PTO output face. As a consequence the pump must have opposite
rotation to that of the PTO.
Some PTO Manufacturers refer the PTO rotation to the rotation of the engine crankshaft. In this case “engine” rotation
coincides with anticlockwise PTO rotation.
SX = Left hand
Anticlockwise
DX = Right hand
Clockwise

10. GEAR POSITION P
It is considered to be a useful detail for a fist sight check of the transmission gear that is supposed to drive the PTO gear.
The catalogue indicates the location of the gear related to the vertical centreline of the PTO opening.
A = FORWARD
C = MIDDLE
P = REARWARD
Front of vehicle

11. PTO SPEED P
It is the rpm that is actually available for driving the installation and it is the parameter that can affect the performance of the whole system.
All the speeds given in the catalogue are calculated considering a nominal engine speed of 1000 rpm.
Some gearboxes can drive the PTO with several different speed ratios, depending on the selected gear. The catalogue lists all available ratios to the PTO.

12. PTO OUTPUT TORQUE P
The available torque at the PTO output depends mainly on the constructional parameters of the PTO.
The torque of the selected PTO should match with the specifications of the driven equipment.
The indicated torque values are Nm and are the maximum available for each output.
Important!
Always make sure that the absorbed torque off the gearbox is lower than the maximum allowed by the gearbox itself. Please contact our technical department for further information.

13. PTO CALCULATIONS
As previously shown, speed and output torque are the main criteria for proper PTO selection.
These factors depend on the technical specifications of the driven equipment.
Some typical PTO driven devices are:
hydraulic pumps
blowers, compressors, generators, etc.

14. DRIVING HYDRAULIC PUMPS
The Flow
In installations operated by single acting or double acting cylinders the required flow Q in litres per minute is:
where V is the required oil volume in litres to accomplish a complete tipping (or any other) operation and t in seconds is the time to complete the same action.
The Pump Capacity
The required pump capacity C in cc/rev is given by the formula:
where Q is the required flow in litres per minute and n in rpm is the PTO output speed.
The Pump Speed
The speed n in rpm of the PTO driven pump is:
where n1 is the PTO output speed at 1000 engine rpm (this value is found in the catalogue) and n2 the engine rpm during the PTO operation.

15. DRIVING HYDRAULIC PUMPS
The Absorbed Torque
The absorbed torque by the system is calculated using the following formula:
where C is the pump capacity in cc/rev, P the pressure in bar (use the setting pressure of the relief valve of the system) and M is the absorbed torque by the pump in Nm.
M must never exceed the value of the PTO torque reported in the catalogue.
Above formula takes into account an average mechanical efficiency of the pump.
Please notice that:

16. DRIVING COMPRESSORS, GENERATORS etc.
Use the following formula to calculate the required torque for driving compressors, generators or any other equipment, when the absorbed horsepower and the operating speed are given:
where n is the equipment speed in rpm and N is the absorbed power in kW.
The resulting torque M absorbed by the equipment must not exceed the value indicated in the catalogue for the selected PTO.
Please notice that:
For special applications, or if you require further instructions or information please call or write our Technical Assistance.

17. PTO OPERATING LIFE PTO’s are designed for a calculated operating
life of 500 working hours at 1000 rpm.
The following diagram indicates the expected
PTO operating life in the case of different operating conditions.
P Required PTO output power in kW
N PTO output speed in rpm
M required torque = ( P / n )
Mn nominal torque, see PTO catalogue
Kt Load coefficient = 100 ( M / Mn )
t PTO expected operating life in hours

18. CONTINUOUS OPERATION ß Absorbed Power (kW)
The duration of continuous, high horsepower PTO operation is restricted by the risk of overheating the Transmission – PTO assembly.
Example: If the required torque N is 300 Nm and the PTO output speed is 1850 rpm, then the power absorbed by the installation is:
= = kW
The following diagram shows the
allowed duration for continuous
operation, depending on the
environment temperature:
0° = 44’ (minutes) max
20° = 24’ (minutes) max
40° = 15’ (minutes) max
N (Nm) x n (rpm)
9552
P (kW) =
300 (Nm) x 1850 (rpm) ß
Absorbed Power (kW)
Environment Temperature (C°)
Continuous Working Time (minutes)

19. PTO OUTPUT OPTIONS

20. PTO OUTPUT OPTIONS DRIVELINE TRANSMISSION FLANGES
DIN Flanges SAE (Spicer) Flanges