Second Edition 03/18/1997 – CSH (con:K2AA V1.0) 031-300-190014_A.doc

LOAD MOMENT INDICATOR

DS 50 / 0002

OPERATOR'S MANUAL

MANITOWOC BOOM TRUCKS, INC.

Second Edition 03/18/1997 – CSH (con:K2AA V1.0) 031-300-190014_A.doc

NOTICE

The information in this document is subject to change without notice.

PAT does not assume any warranty of any kind with regard to this material, including, but not

limited to the implied warranties of marketability and fitness for a particular purpose.

PAT shall not be liable for errors contained herein or for incidental or consequential damages in

connection with the furnishing, performance or use of this manual.

This document contains proprietary information, which is protected by copyright. All rights

reserved.

No part of this document may be photocopied, reproduced, or translated to another language

without the prior written consent of PAT.

Second Edition 03/18/1997 – CSH (con:K2AA V1.0) 031-300-190014_A.doc

TABLE OF CONTENTS

1

General Information

2

2 Warnings

2

3

System Description

3

3.1 System

Function

5

3.2 Control

Identification

6

4 Pre-Operational

Inspection

9

4.1

Anti two-block devices

9

4.2

Pre- Operation Inspection and Calibration Verification

10

5 System

Operation

12

5.1

Operating Mode Selection

12

5.2

Selection of the Reeving

13

5.3 Data

Display

14

5.4 Error

Display

15

5.5

System and Display test

15

6

Service and Maintenance

15

7 Troubleshooting

16

Operator's Manual

DS 50 / 0002

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1 GENERAL INFORMATION

The PAT Load Moment Indicator

1

(LMI) DS 50 has been designed to provide the crane operator with the

essential information required to enable the machine to be used within its design parameters.

Using different sensing devices, the Load Moment Indicator monitors various crane functions and provides
the operator with a continuous reading of the capacity of the crane. The readings continuously change as
the crane moves through the motions needed to make the lift.

The LMI provides the operator with information regarding the length and angle of the boom, working
radius, rated load and the total calculated weight being lifted by the crane.

If non-permitted conditions are approached, the DS 50 Load Moment Indicator will warn the operator by
sounding an audible alarm and lighting a warning light.

Always refer to operational instructions and load charts provided by the crane manufacturer for
specific crane operation and load limits.

2 WARNINGS

The LMI is an operational aid that warns a crane operator of approaching overload conditions and warns of
overhoist conditions which could cause damage to equipment and personnel.

The device is not, and shall not be, a substitute for good operator judgment, experience and use of
accepted safe crane operating procedures.

The responsibility for the safe crane operation shall remain with the crane operator who shall ensure that
all warnings and instructions supplied are fully understood and observed.

Prior to operating the crane, the operator must carefully and thoroughly read and understand the
information in this manual to ensure that he knows the operation and limitations of indicator and crane.

Proper functioning depends upon proper daily inspection and observance of the operating instructions set
forth in this manual. We draw your attention to section 5 of this manual.

1

LOAD MOMENT: generally, the product of a force and its moment arm; specifically, the product of the load and the load-radius. Used in the

determination of the lifting capacity of a crane.

Operator's Manual

DS 50 / 0002

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3

The LMI can only work correctly, if all adjustments have been properly set. For correct
adjustment, the operator has to set the operating code and the parts of line (reeving) thoroughly
and correctly in accordance with the real rigging state of the crane. To prevent material damage
and serious or even fatal accidents, the correct adjustment of the LMI has to be ensured before
starting the crane operation

3 SYSTEM DESCRIPTION

The PAT Load Moment Indicator DS 50 consists of a central micro processor unit with build in length- and
angle sensor, operating console, pressure transducers, and anti-two block switch(es).

The system operates on the principle of reference/real comparison. The real value, resulting from the
pressure measurement is compared with the reference data, stored in the central processor memory and
evaluated in the microprocessor. When limits are reached, an overload-warning signal is generated at the
operator’s console.

The fixed data regarding the crane, such as capacity charts, boom weights, centers of gravity and
dimensions are stored in memory chips in the central processor unit. This data is the reference information
used to calculate the operating conditions.

The length/angle sensor mounted inside the cable reel, which is mounted on the boom registers boom
length and boom angle. The boom length is measured by the cable reel cable, which also serves as an
electrical conductor for the anti two-block switches.

Pressure transducers attached to the piston and rod sides of the hoist cylinder measure the crane load.

The console has two functions:
• displays information to the operator

• input terminal for operating mode and reeving (parts of line)

The operator’s console is mounted in the operator’s field of vision. For a better identification of displays
and operating elements, they are continuously backlit during operation.

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DS 50 / 0002

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Fig. 1: Components of the LMI system PAT DS 50

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3.1 System Function

Upon switching on, the system starts with an
automatic test of the LMI system, of lamps
and audible alarm.

During the test, the LC display shows

8:88.8.8

First, the operating mode is determined by
input of the operating code number

System awaits acknowledgment

Next is the selection of the reeving

System awaits acknowledgment

Upon acknowledgment of the inputs, the
system is ready for operation.

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DS 50 / 0002

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3.2 Control Identification

This unit contains a display and different controls that are described as follows:


Fig. 2: Operating Console

1 LC Display
2 Load Moment Limit Light
3 Load Moment Prewarning Light
4 Alarm Light “Anti-Two-Block”
5 Button “UP”
6 Button “DOWN”
7 Button and Control Light “OK”
8 Button and Control Light “SELECT OPERATION CODE”
9 Button and Control Light “SELECT REEVING”

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LC-Display

The LC Display has five digits. The
readout depends on the operating modus
and the operator’s selection.
Please refer to section 4, Operation of the
system.

Load Moment Limit Light

The red LOAD MOMENT LIMIT LIGHT (2) warns the
operator that a rated load condition has been
reached. It lights up when the load on the crane
reaches the crane load capacity. The audible alarm
also sounds when this condition has been reached.

Load Moment Prewarning Light

The yellow LOAD MOMENT PRE-WARNING LIGHT
(3) will light up when the load on the crane reaches
the defined prewarning area, thus indicating that an
overload condition is approaching.
This means for the operator to continue his crane
operation with extreme caution.

Alarm Light “Anti-2-Block”

The red “Anti Two-Block Alarm Light” (4) lights up
when the anti-two-block limit switch contacts open,
indicating that a two-blocking condition is
approaching. At the same time, the audible alarm will
sound, and the telescope out and winch up functions
are locked out. If machine is equipped with an
overload shut-off, the boom down function is also
locked out.

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DS 50 / 0002

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Cursor

"up"

Key for the stepwise increase of the displayed value:
• when selecting the operation code

• when selecting the reeving

• when selecting the geometry data

(

➭ refer to chapter 5.3)

Cursor

"down"

Key for the stepwise decrease of the displayed value:
• when selecting the operation code

• when selecting the reeving

• when selecting the geometry data

(

➭ refer to chapter 5.3)

Button

“OK”

Key for acknowledgment of an error message.

The correct setting of the operation mode and the reeving is of utmost importance for
the proper function of the system and the crane. Therefore, only operators who are
thoroughly familiar with use and operation of the system shall set the following buttons:

Button " set operating mode"

Button to start the function "set operating mode ".
For the proceeding, please refer to

➭ chapter 5.1.

Button "set reeving"

Button to start the function "set reeving" (parts of
line).
For the proceeding, please refer to

➭ chapter 5.2.

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4 Pre-Operational Inspection

Prior to operating the crane, the following electrical connections must be checked to ensure that the
system is properly connected for the crane configuration.

4.1 Anti two-block devices

If the crane works only with the main boom and without boom extension, check the weight to ensure it is
attached to the anti two-block switch on the main hoist load line.

Weight installation - The hoist line runs through the A2B weight. With even parts of hoisting line, the weight
shall be attached to the dead-end line. With odd parts of hoisting line, the weight shall be attached to the
line of lowest speed.

If an extension exists, install the connecting cables between the boom extension junction box and the
boom point junction box. Remove the weight from the main boom anti-two block switch and re-attach it to
the boom extension anti-two block switch on the auxiliary hoist line.

Failure to position the anti two-block switch weight will prevent the overhoist system from functioning
properly. No weight shall be on the main hoist anti two-block switch when the boom extension is being
used.

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4.2 Pre-Operation Inspection and Calibration Verification

After the electrical connections have been checked to insure that the system is properly connected for the
crane configuration, the following checks shall be made:

1. Check the electrical wiring connecting the various parts of the system for physical damage.
2. Check the anti two-block switches and weights for free movement.
3. Check the spring-loaded cable reel to be sure it is free to rotate, has tension and the cable is reeled

properly.

The following tests shall be performed with care to prevent damage to the machine or injury to

personnel. Proper functioning of the system requires successful completion of these tests
before operating the machine.

4. Check the anti two-block alarm light (4) and the audible alarm by performing one of the following tests

a, b, or c. If the crane is equipped with a boom extension, perform the test procedure on both the main
boom and boom extension anti two-block switches.

When checking system the operator must use caution. If the operator cannot see the load-handling device
approaching the boom nose, he/she shall have an assistant (signal person) watch the load handling
device. The operator shall be prepared to stop the machine immediately should the LMI system not
function properly. Proper operation will be indicated by:
• lighting the red warning light (4)

• sounding the audible alarm

• locking out of the hoist up and telescope out functions

• and if the overload shutoff option is installed, a lockout of the boom down function will occur

a) By manually lifting the weight attached to the anti two-block switches. When the weight is lifted, the

audible alarm should sound, the anti two-block alarm light (4) should light.

b) Slowly raise the main boom load-handling device to create a potential two-block condition. When the

load-handling device lifts the weight, the audible alarm should sound, the anti two- block alarm light (4)
should light and the motion of the load handling device should be stopped. Lower the load-handling
device slightly or telescope the boom in to eliminate this condition.

c) Slowly extend (telescope) the boom to create a potential two-block condition. When the load-handling

device lifts the weight, the audible alarm (17) should sound, the anti two-block alarm light (24) should
light and the boom telescope out function should be stopped. Lower the load-handling device slightly or
telescope the boom in to eliminate this condition.

NOTE: If the crane is equipped with the overload shutoff option, a two-block condition will also lockout the
boom down function. If operating properly, the lockout feature will always permit operation of the hoist
down, telescope in, and boom up functions.

If the light and audible alarm do not function as described and the crane movements are not
stopped, the system is not working properly. The malfunction shall be corrected before
operating the crane.

Operator's Manual

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5. Check that the display of the main boom length agrees with the actual boom length.
6. Check that the display of the main boom angle agrees with the actual boom angles.
7. Check that the display of the operating radius of the crane agrees with the actual radius.
8. Check the load display by lifting a load of known weight. The accuracy of the load indication shall be

within the tolerance of SAE J159.

After being properly checked, the LMI is operational. The operator shall be thoroughly familiar with all
controls of the LMI before operating the crane (see Section 3.2). Lifting a load of known weight and
comparing the load to the information displayed on the LMI (see Section 5.2) shall check the proper
function of the system.

Rated loads include the weight of the hook block, slings, and auxiliary load handling devices. Their
combined weights shall be subtracted from the listed load capacities as stated on the load capacity chart to
obtain the net load to be lifted.

If any of the displays reflects a deviation between displayed and actual values, an authorized
PAT service representative shall be called for repair of the system and/or verification of the
crane’s LMI calibration.

Any structural modifications or changes to the crane shall require verification of the
LMI calibration of the crane.

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DS 50 / 0002

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5 SYSTEM OPERATION

The LMI System DS 50 allows the operator to assess and evaluate the lift to meet the manufacturer
specified load charts for the crane.

The correct setting is of utmost importance for the proper functioning of the system and the
crane. Therefore, the crane must not be operated without setting the appropriate operating
code.

5.1 Operating Mode Selection

start function:

(automatically after system start)

• Manually at each modification of the crane

configuration by pressing key,

The operating mode key and the cursor keys
light up. The operating mode selection is
displayed:

XX= present operating code

select mode:

• use cursor keys

and

to modify

the operating code

confirm

selection:

• By pressing again, key

.

The cursor keys and the operating selection
key go out.

NOTE: If the system is turned off, all
adjustments remain stored. When the system
is turned back on, the adjustments can be

acknowledged by merely pressing key:

(if the crane configuration has not been
modified!).

Troubleshooting

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5.2 Selection of the Reeving (parts of line)

start function:

(automatically after finishing operation mode
selection)

manually upon modification of the reeving by

pressing key

The reeving key and the cursor keys light up. The
reeving selection is displayed:

XX= present reeving

select

reeving:

• use cursor keys

and

to modify

the reeving

confirm

selection:

By pressing again, key

.

The cursor keys and the reeving key go out.

NOTE: If the system is turned off, all adjustments remain stored. When turning on again the system these

adjustments can be acknowledged by merely pressing keys:

and then

Verify the operating mode and reeving displayed with the configuration of the crane.

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5.3 Data Display

In case neither the operating mode selection nor the reeving selection are active, the LC display serves as
data display:

Press keys

and

to select the values. There are 9 display positions:

Display Position

Y

Displayed Value

XXXX

0 error

message

1

main boom length

2

main boom angle

3 radius
4

utilization in %

5 tip

height

6 capacity
7 actual

load

8 load

moment

Troubleshooting

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5.4 Error Display

In case of operating error or system malfunction an error code is displayed. (for detailed information refer
to chapter 7 troubleshooting)
Error messages are given priority on the display:

XX=error

code

Press key

to acknowledge an error message (exception: console error messages)

5.5 System and Display Test

Press keys

and

simultaneously to select the test function.

All lamps light up, the buzzer is turned on and the following is displayed:

During the test, the data transmission to the central unit is interrupted so that 2 seconds later approx. the
cutoff relay is de-energized.

6 SERVICE AND MAINTENANCE

Daily maintenance of the load moment indicator consists of inspecting:

• The electrical wiring connecting the various parts of the system.

If electrical wiring is damaged, it shall be replaced immediately.

• If the insulation is worn on the length sensor cable or cable guides are damaged, these parts shall be

replaced.

• Check the anti two-block limit switches for freedom of movement.

• The cable reel shall be under tension to operate properly.

• Check the pressure transducers at the hoist cylinder and the connecting hoses for oil leakage.

Other than correcting the problems identified in the Malfunctions Table and replacing faulty mechanical
parts and cables, no other repairs shall be performed by non-expert personnel.

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DS 50 / 0002

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7 TROUBLESHOOTING

General

In case of a malfunction of the system, the display (1) will indicate a code that identifies the system
malfunction.

The error codes listed in the Malfunction Table will identify various faults that can occur with the LMI.
Following the Malfunction Table are pages that explain each fault and describe the action that shall be
taken to correct the fault.

Faults within the electronic microprocessor shall be repaired by factory trained service personnel. When
these faults occur, the competent service organization shall be contacted.

Malfunction Table

Error Code Error

E01

Fallen below the radius or above angle range

E02

Radius range exceeded or fallen below angle
range

E03

Boom position is out of the permissible working
area

E04

Operating mode not existing

E05

Prohibited length range

NOTE:

If there is any Error Code displayed on the console which is not listed in the Malfunctions Table
you shall call the Local Distributor.

Troubleshooting

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Operating Errors

Malfunctions in the system that are caused by range exceeding or operating errors by the crane operator
himself are indicated on the display. These error codes are E01, E02, E03, E04, and the crane operator
himself can normally eliminate E05 and them.

Error

Code

Cause Elimination

E01

Fallen below the minimum
radius or above the angle given
in the load capacity chart due to
luffing up the boom too far.

Luff down boom to a radius or
angle given in the load capacity
chart.

E02

The maximum radius or
minimum angle given in the load
capacity chart was exceeded
due to luffing down the boom
too far.

Luff up boom to a radius or
angle given in the load capacity
chart.

E03

Boom position is out of the
permissible working area (over
front).

Move boom back to the
permissible working area. See
lifting diagram in the load
capacity charts.

E04

Operating mode at the console
incorrectly set.

Correctly set operating mode to
the code assigned to the
operating mode of the crane.

Operating mode is not
permissible with the actual
crane configuration or boom
position

Be sure crane is set up
according to proper operating
configurations.

E05

Boom was telescoped too far or
not far enough, you may only
operate up to a certain
maximum or minimum boom
length or with load curves for
boom extension where you have
to telescope the main boom to a
certain length.

Telescope boom to correct
length, given in the load
capacity chart.

Length sensor adjustment
changed i.e. length sensor cable
slid off the length sensor drum.

For elimination, refer to service
manual.