Cat X-4114 BRAKE MONITORING SYSTEM OPERATING INSTRUCTIONS MANUAL BI619720

BI619720

X-4114 BRAKE MONITORING SYSTEM OPERATING INSTRUCTIONS FOR IGBT SHOVELS

Approved By: JCV:XI4:01:602

-1-

Issued March, 2001 X-4114

BI619720

Foreword The following X-Instructions contain general information that will allow the reader to have a basic understanding of the brake monitoring system that is currently being used on the IGBT shovels.

For more detailed information, refer to the applicable schematics, drawings, PLC program listing, Operator’s Manual, Operator Display Manual or Maintenance Manual as necessary.

JCV:XI4:01:601

-2-

Issued March, 2001 X-4114

BI619720

Table of Contents Foreword

.

.

.

.

.

.

.

.

.

Page 1

.

.

.

.

.

.

.

.

Page 2

.

.

.

.

.

Page 3

.

.

.

.

Page 4

Brake Monitoring System Electrical Commissioning .

.

.

Page 6

Brake Monitoring System Troubleshooting .

.

.

.

Table of Contents

Brake Monitoring System Configuration

Brake Monitoring System Theory of Operation.

JCV:XI4:01:601

.

-3-

Page 9

Issued March, 2001 X-4114

BI619720

Brake Monitoring System Configuration The brake monitoring system is controlled by a PLC that also controls all of the machine’s auxiliary functions.

The shovel has brake monitoring componentry on the brakes for the Hoist, Crowd, and Swing motions. There is no monitoring of the Propel brake(s).

The general functions of the brake monitoring equipment are as follows: There is a release indicator that gives positive indication of brake release. The status of this indicator is a permissive for machine startup / operation.

There is a wear indicator that checks to see if the brake has worn to a point that requires adjustment or replacement.

There is an over-temperature sensor that monitors the temperature of the brake’s wear plate or center plate.

More detailed information follows in the “Brake Monitoring System Theory of Operation” section.

JCV:XI4:01:601

-4-

Issued March, 2001 X-4114

BI619720

Brake Monitoring System Theory of Operation Note: Refer to the applicable electrical schematics and reference documents as necessary throughout this section.

As mentioned in the previous section, there is brake monitoring equipment installed for the Hoist, Crowd, and Swing brakes of the shovel. This amounts to a brake release indicator, a brake wear indicator, and a brake over-temperature sensor for each of the aforementioned brakes. The brake monitoring package is not installed on the Propel brake(s).

Brake Release Indicator: The function of the brake release indicator is to give a signal to the PLC that is a positive indication of brake release. The status of this indicator is a permissive for machine startup and operation as follows: 1)

If the brake release indicator is adjusted properly, the indicator contact closes when the brake is released and opens when the brake is set.

2)

Release of control will not be allowed if the DC bus is up and one of the brakes is sensed as being released. In addition to this, if a brake is sensed as being released with the bus up and control off, the operator’s display will display a “Brake Released with Control Off” fault for the corresponding motion. This type of fault message will not be displayed unless the DC bus is up.

3)

If the operator brings “control on” during the normal start up sequence of the shovel, and then puts a brake switch in the release position, brake release must be sensed within one second or a “brake release fault” will occur. If control is on and the brake is not sensed as being released within the one second time frame, all motions will be gate blocked. The brake release fault will be displayed for the particular motion as a message on the Operator Display. The un-faulted motions can then be restarted.

4)

If brake release is not sensed, the master switch reference would not be released to the corresponding drive.

5)

If the brake release indicator is bypassed, due to indicator failure, the Operator Display will display this as a warning message for either the Hoist, Crowd, or Swing motions. The message will be something like “Hoist Brake Limit Switch Disabled.”

Brake Wear Indicator: The function of the brake wear indicator is to give a signal to the PLC that is an indication of whether or not the brake requires an inspection, adjustment or replacement. The operation of this indicator is as follows:

JCV:XI4:01:601

-5-

Issued March, 2001 X-4114

BI619720

1)

The brake wear indicator contact is open assuming that it is adjusted properly and that the brake is in good operating condition. The contact closes when excessive brake wear has been sensed and the brake is in the set position.

2)

If upon brake set, the wear indicator switch senses that the brake has worn beyond a certain point, the Operator Display will display a “brake worn” warning for the particular motion. This warning does not generate any type of machine shutdown.

It is only an indication that the brake should be inspected for wear.

3)

The brake wear indicator is only operational when the brake is set. It is not active during machine operation.

CAUTION: The wear indicator is a warning device only and does not eliminate the need for proper preventative maintenance. All procedures called for on the brake general arrangement drawings must still be followed, including physical measurement of brake wear.

Brake Over-Temperature Sensor: There is an over-temperature sensor that monitors the temperature of the brake”s wear plate on a single disc brake or the center plate on a multi-disc brake. The function of the over-temperature sensor is to give a signal to the PLC that is an indication of whether or not the brake temperature is within the required operating range as follows: 1)

If brake temperature is within normal operating range the sensor contact is closed.

When an over-temperature occurs, the sensor contact opens.

2)

A brake over-temperature condition is sensed whenever the indicator temperature exceeds 300° +/- 5° Fahrenheit.

3)

When a brake over-temperature occurs, the over-temperature sensor contact opens which triggers the PLC to put the shovel into a delayed shutdown mode. This gives the operator 30 seconds to park the shovel in a serviceable position, or the motions are shut down via the PLC after this time. At this time, a “brake overtemperature” message is displayed on the Operator Display for the appropriate motion.

4)

Un-faulted motions can be restarted immediately following the delayed shutdown.

The faulted motion will be allowed to restart once the over-temperature sensor contact re-closes, which is 5° Fahrenheit below the opening point.

JCV:XI4:01:601

-6-

Issued March, 2001 X-4114

BI619720

Brake Monitoring System Electrical Commissioning Notes: It is assumed that the brake release indicators and brake wear switches have been adjusted as per the mechanical general arrangement drawings before proceeding. Refer to the applicable electrical schematics and reference documents as necessary throughout this section.

1)

Make sure that all power is isolated from the brake monitoring system components, PLC and related brake monitoring system wiring.

2)

Check the integrity of all electrical wiring associated with the brake monitoring system.

This would include: Proper termination points Tight connections No grounded signal wires No short circuits Proper grounding

CAUTION: Before proceeding it is assumed that the integrity of all PLC wiring has been checked as per the normal commissioning procedure, and that the CVT has been commissioned. Lockout / tagout devices as necessary to ensure that injury or equipment damage does not result.

WARNING: Ensure that motion movement cannot occur when brakes are released during this procedure or damage to the equipment and/or injury to personnel could result.

3)

Energize the PLC rack by closing

4)

Make sure that the PLC outputs are active. Refer to the electrical schematics as necessary.

5)

Clear any active alarms on the Operator Display that will not allow machine start up.

6)

Making sure that motion movement cannot occur, manually release the Hoist brake.

7)

Bring up the DC bus.

8)

A “Hoist Brake Released With Control Off” fault should be present on the Operator Display.

9)

Verify that control is not released when control reset is pressed in the operator’s cab.

10)

Verify that the fault clears when the Hoist brake is set.

JCV:XI4:01:601

Q23 in MRC for Crowd & Swing 1 Q24 in MRC for Hoist & Swing 2

-7-

Issued March, 2001 X-4114

BI619720

11)

Repeat steps 5 - 10 for the Crowd and Swing Brakes. A fault similar to the one in step 8 should occur, except that it will be applicable to either the Crowd or one of the Swing brakes.

12)

Clear any active alarms on the Operator Display that will not allow machine start up.

13)

Bring up the DC bus.

14)

Make sure that all brake switches are in the set position.

15)

Go to the “operator’s display” screen on the Operator Display if not there already.

16)

Transfer into the “dig” mode of operation if not there already.

17)

Press the “control reset” push-button. The “control released” indicators on the Operator Display for the Hoist, Crowd and Swing motions should be illuminated.

18)

Move the Hoist Brake Switch to the release position. Within a few seconds, the “hoist brake released” indicator should be illuminated on the Operator Display.

19)

Move the Hoist Brake Switch back to the set position. The “hoist brake released” indicator on the Operator Display should not be highlighted, which signifies that the hoist brake has set.

20)

Move the Crowd Brake Switch to the release position. Within a few seconds, the “crowd brake released” indicator should be illuminated on the Operator Display.

21)

Move the Crowd Brake Switch back to the set position. The “crowd brake released” indicator on the Operator Display should not be highlighted, which signifies that the Crowd brake has set.

22)

Move the Swing Brake Switch to the release position. Within a few seconds, the “swing brake released” indicator should be illuminated on the Operator Display.

23)

Move the Swing Brake Switch back to the set position. The “swing brake released” indicator on the Operator Display should not be highlighted, which signifies that the Swing brake has set.

24)

Press the “control-stop” push-button. The “control released” indicators on the Operator Display should not be highlighted. This signifies that motion control is off.

25)

Press one of the BEB push-buttons so that the DC bus discharges.

JCV:XI4:01:601

-8-

Issued March, 2001 X-4114

BI619720

26)

Making sure that motion movement cannot occur, manually release the Hoist brake.

27)

Insert a piece of 1/8" flat stock between the Hoist Brake Wear Indicator and it’s corresponding bracket.

28)

Set the Hoist brake. This should cause the Hoist Brake Wear Indicator internal contact to close.

29)

The message “Hoist Brake Worn Indication” should appear on the Operator Display. This is only a warning and does not cause a drive shutdown.

30)

Manually release the Hoist brake and remove the flat stock.

31)

Set the Hoist brake.

32)

Repeat steps 26 - 31 for both the Crowd and the Swing brakes. A similar warning message should appear on the Operator Display, except that it should be related to the motion under test.

JCV:XI4:01:601

-9-

Issued March, 2001 X-4114

BI619720

Brake Monitoring System Troubleshooting Note: Refer to the applicable electrical schematics and reference documents as necessary throughout this section.

Troubleshooting of the system will be necessary when a brake monitoring system related message appears on the Operator Display. These messages are as follows: Hoist Brake Not Set With Control Off Crowd Brake Not Set With Control Off Swing Brake 1 Not Set With Control Off Swing Brake 2 Not Set With Control Off Hoist Brake Release Fault Crowd Brake Release Fault Swing Brake 1 Release Fault Swing Brake 2 Release Fault Hoist Brake Limit Switch Disabled Crowd Brake Limit Switch Disabled Swing Brake Limit Switches Disabled Hoist Brake Worn Indication Crowd Brake Worn Indication Swing Brake 1 Worn Indication Swing Brake 2 Worn Indication Hoist Brake Over-temperature Crowd Brake Over-temperature Swing Brake 1 Over-temperature Swing Brake 2 Over-temperature By the list of messages above, it can be seen that there are five similar type messages per motion.

The PLC logic for each particular type of message is functionally the same. The troubleshooting procedure for each type of message is as follows: Brake Not Set With Control Off fault displayed on Operator Display Release of control is not allowed if the DC bus is up and one of the brakes is sensed as being released.

Probable Cause

Probable Solution

1)

The brake was manually released during a maintenance procedure.

1)

Manually set the brake that was released.

2)

The brake release indicator is misadjusted.

2)

Readjust the position of the indicator as per the proper mechanical general arrangement drawing.

3)

The brake release indicator is faulty.

3)

Replace the brake release indicator.

JCV:XI4:01:601

- 10 -

Issued March, 2001 X-4114

BI619720

Brake Release Fault displayed on Operator Display The function of the brake release indicator is to give a signal to the PLC that is a positive indication of brake release. If the brake release indicator contact does not close (signifying brake release) within one second after the brake valve energizes, this fault occurs.

Probable Cause

Probable Solution

1)

The brake release indicator is misadjusted.

1)

Readjust the position of the indicator as per the proper mechanical general arrangement drawing.

2)

There is an air delivery problem to the brake valve.

2)

Repair air line or air compressor problem.

3)

There is an open connection in the brake release indicator or brake valve circuitry.

3)

Revise the circuitry as per the electrical schematics.

4)

The brake valve solenoid is faulty.

4)

Replace the brake valve solenoid.

5)

The brake release indicator is faulty.

5)

Replace the brake release indicator.

Brake Limit Switch Disabled warning displayed on Operator Display If the brake release indicator is bypassed, due to brake release indicator failure, the Operator Display will display this as a warning message for either the Hoist, Crowd, or Swing motions.

Refer to the electrical schematics for more information.

Brake Worn Indication warning displayed on Operator Display The function of the brake wear indicator is to give a signal to the PLC that is an indication of whether or not the brake requires an inspection, adjustment or replacement. The contact closes when excessive brake wear has been sensed and the brake is in the set position.

Probable Cause

Probable Solution

1)

The brake requires an inspection.

1)

Adjust the brake or replace failed brake components as necessary.

2)

The brake wear indicator is misadjusted.

2)

Readjust the position of the indicator as per the proper mechanical general arrangement drawing.

3)

The brake wear indicator is faulty.

3)

Replace the brake wear indicator.

JCV:XI4:01:601

- 11 -

Issued March, 2001 X-4114

BI619720

Brake Over-temperature fault displayed on Operator Display The function of the over-temperature sensor is to give a signal to the PLC that is an indication of whether or not the brake temperature is within the required operating range. If brake temperature is within normal operating range the sensor contact is closed. When an over-temperature occurs, the sensor contact opens. A brake over-temperature condition is sensed whenever the indicator temperature exceeds 300° +/- 5° Fahrenheit.

Probable Cause

Probable Solution

1)

The brake has a mechanical problem.

1)

Repair or adjust as necessary.

2)

Overheating being caused by excessive drive or system related faults.

2)

Repair the drive or system related faults.

3)

There is an open connection in the brake over-temperature sensor circuitry.

3)

Revise the circuitry as per the electrical schematics.

4)

The brake over-temperature sensor is faulty.

4)

Replace the brake over-temperature sensor.

JCV:XI4:01:601

- 12 -

Issued March, 2001 X-4114