Troubleshooting Guide for Leaks in the Vacuum of Certain UPS Systems{4287} Caterpillar

Uninterruptible Power Supply:

ES12F (S/N: CZE1-UP)

UPS 1000S (S/N: CZS1-UP)

UPS 1000Z (S/N: EDZ1-UP)

UPS 120 (S/N: CNK1-UP)

UPS 1200S (S/N: CZT1-UP)

UPS 1200Z (S/N: HDR1-UP)

UPS 150 (S/N: CPC1-UP)

UPS 250 (S/N: BEE1-UP; CNM1-UP; APZ1-UP)

UPS 300 (S/N: CNJ1-UP; CPZ1-UP)

UPS 301 (S/N: CSY1-UP)

UPS 500 (S/N: CSE1-UP)

UPS 600 (S/N: CTX1-UP)

UPS 750 (S/N: CPM1-UP)

UPS 900 (S/N: CRY1-UP)

UPS500G (S/N: TYD1-UP)

UPS600G (S/N: DLD1-UP)

Introduction

This Special Instruction provides information for troubleshooting vacuum leaks on the modules that are listed above.

Important Safety Information

Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs.

A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools in order to perform these functions properly.

Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard.

Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. If a tool, a procedure, a work method, or operating technique that is not recommended by Caterpillar is used,ensure that it is safe for you and for other people to use.

Ensure that the product will not be damaged or the product will be made unsafe by the operation, lubrication, maintenance, or the repair procedures that are used.

Required Parts

The parts that are required for the correction of a leak on the vacuum are listed in Table 1.

Required Tools

The tools that are required for the correction of a leak on the vacuum are listed in Table 2.

Troubleshooting Procedures

Some possible causes of a loss of vacuum are:

General Causes

• Impurities in the oil.

• Water vapor has contaminated the oil.

• The oil is past due to be changed.

• A vacuum leak exists in the system.

• A damaged O-ring for the sensor needs to be replaced.

• The pump has been running at a high vacuum for a long period.

• The pump has been replaced.

• The vacuum pump has been idle or in storage for 2+ months.

• The two screws on the sight glass may be improperly torqued. The specification is 8 N·m (6 lb ft).

Note: Be sure to brake the flywheel, so comes to a complete stop. Then place the UPS in Bypass. After 5 minutes time, then proceed with the troubleshooting procedure.

Common Causes at Startup

• The O-Ring may not come out with the shipping retainer when removed. If the shipping retainer O-Ring is not verified removed, it may cause two O-Rings to be installed after the bearing is installed.

• RPS sensor O-Ring.

• Load cell O-Ring. If the O-Ring slips out of the retaining groove, it can be damaged when bolts are tightened.

Common ways to help prevent a Vacuum Loss

• When installing the bearings, load cell, and RPS sensor, insure the O-Ring stays in the retaining groove.

• Be careful not to bump any of the armature pins. Bumping the armature pins could cause a pin leak.

• Clean and grease all O-Rings, when appropriate. Apply grease so there is only a thin film on the O-Ring.

Note: Excessive use of grease does not improve vacuum, and may in fact cause a vacuum leak.

• When checking the SAE plugs, insure they are not over torqued (47 N·m (35 lb ft)). Over torquing can cause a leak or make an existing leak worse.

Note: Always start on the bottom flywheel if you are checking a unit that has dual flywheels.

CHECK FOR LEAKS ON THE TOP OF THE FLYWHEEL

The instructions to perform leak checks at the top of the flywheel are given below:

Note: Use Methanol to perform Vacuum Troubleshooting whenever possible. If Methanol is not available, only use 91% Isopropyl Alcohol or greater as a last resort. The higher the % the better.

Note: When applying alcohol or methanol, insure that no alcohol or methanol gets in the RPM sensor or the Vacuum Gauge. If alcohol or methanol gets inside these sensors/gauge, the sensor/gauge will give a false reading. Use a swap to apply the alcohol or methanol to prevent the alcohol or methanol from getting inside of these sensors/gauges.

When using alcohol or methanol to check for vacuum leaks, the procedure is as follows:

1. Apply alcohol or methanol to test area.

2. Monitor Vacuum mTorr Readings.

3. If Vacuum mTorr reading momentarily deflects for 5 mTorr or more, then the vacuum leak has been located and follow the rest of the instructions.

4. After performing the corrective action, recheck the vacuum.

5. If the mTorr reading does not deflect 5 mTorr or more, proceed to the next troubleshooting step.

Note: Determine if maintenance was performed on the unit before the issue of the leak. Record all of the elements that changed during the maintenance.

Note: Proceed to deadhead the vacuum pump if the vacuum is broken at any point in the procedure.

Note: Wait for 30 seconds to 1 minute between each of the steps in order to prevent incorrectly identifying an issue.

1. Remove the cable from the bearing thermistor before you apply the methanol. Apply a small amount of methanol to the bearing thermistor. Replace the bearings if the thermistor is the source of the leak.

2. Apply a small amount of methanol to the outside of the plate for the rotor position sensor. Replace the O-ring and apply grease to the new O-ring if the seal is the source of the leak.

3. Apply a small amount of methanol to the entry for the fiber optic tube on the rotor position sensor. Replace the rotor position sensor if the sensor is the source of the leak.

4. Apply a small amount of methanol to all of the 90 degree elbows that are on the pump. If the Output nozzle is good and the Input nozzle is not, switch the Input nozzle and the Output nozzle. Then order the replacement nozzle and replace when part arrives. Replace the elbows if the elbows are the source of the leak. Torque the exhaust and the intake to 13.6 N·m (10.00 lb ft).

5. Apply a small amount of methanol to the four SAE plugs. Replace the O-ring and apply grease to the new O-ring if the plug is the source of the leak.

6. Apply a small amount of methanol to the connector for the top field coil. Apply a silicon sealer to the connection for the top field coil if the field coil is the source of the leak.

   Note: Refer to REHS4872, ""REPAIR A LEAK ON THE POST FOR THE FIELD COIL" ".

7. Apply a small amount of methanol to the edge of the cartridge for the upper bearing. Replace the O-ring and apply grease to the new O-ring if the bearing is the source of the leak.

Note: Check the 152.4 mm (6.00 inch) jumper hose and the clamps that are used in order to connect the flywheels if you are checking a dual flywheel system. Replace the parts.

CHECK FOR LEAKS ON THE BOTTOM OF THE FLYWHEEL

1. Check for leaks at the bottom of the flywheel.

   Note: Always start on the bottom flywheel if you are checking a system with dual flywheels.

   Note: Remember that gravity is working against you. Too small of an amount (an amount that might have been OK on the top) may not be enough to penetrate a leak to make a difference in the reading.

2. Apply a small amount of methanol to the armatures. If a leak is found, use 2-ton epoxy in order to repair the leak.

3. Apply a small amount of methanol to the end plate for the cartridge on the load cell. Replace the O-ring and apply grease to the new O-ring if the bearing is the source of the leak.

4. Apply a small amount of methanol to the center plug on the load cell. Replace the O-ring and apply grease to the new O-ring if the plug is the source of the leak.

5. Apply a small amount of methanol to the three SAE plugs and the port for the vacuum. Replace the O-rings and apply grease to the new O-rings if the plugs and the port for the vacuum are the source of the leak.

6. Apply a small amount of methanol to the 10-pin connector for the Load cell. Replace the O-ring and apply grease to the new O-ring if the connector is the source of the leak.

7. Apply a small amount of methanol to the 10-pin connector for the flywheel. Replace the O-ring and apply grease to the new O-ring if the connector is the source of the leak.

8. Apply a small amount of methanol to the connector for the bottom field coil. Apply a silicon sealer to the connection for the bottom field coil if the field coil is the source of the leak.

   Note: Refer to REHS4872, ""REPAIR A LEAK ON THE POST OF THE FIELD COIL" ".

9. Spray the vacuum hose with methanol in order to check for small leaks. Replace the hose if the hose is the source of the leak.

10. Check the connection of the hose clamps for the vacuum. Tighten the clamps if the clamps are loose.

11. Check the vacuum gauge for a leak. Apply new PTFE tape to the connection and apply new grease to the O-ring if the gauge is the source of the leak.

CHANGE THE OIL IN THE VACUUM PUMP

Note: Purging the system for too long can cause oil from the vacuum pump to spit up into the exhaust hose and onto the floor at the end of the exhaust hose.

1. Change the oil in the vacuum pump. Refer to the Testing and Adjusting, RENR9988, "Uninterruptible Power Supply" for more details on procedure.

2. The ballast should be set to "0" position for maybe 5-10 minutes. This basically is pulling a vacuum to a stable level.

3. Open the ballast to position "II". The vacuum will rise slightly.

4. Once the vacuum stabilizes with the ballast in position "II" and begins to bring the vacuum level back down, then close the ballast to the "0" position.

Note: If the vacuum pump has taken in considerable air or moisture, the technician will likely see white smoke (vapor) coming out from under the UPS at the end of the exhaust hose when the ballast is opened. This is normal and will taper off as the air/moisture is removed from the system. The vapor that comes out can set of Fire Detection Systems located in the room.

5. Verify that the vacuum has dropped to an acceptable operating level below 25 mTorr.

6. Place the flywheel in the "Online" mode.

7. Verify that the vacuum is still below 25 mTorr.

8. Allow the vacuum to stabilize for a minimum of 3 hours. A minimum of 6 hours is required for a dual flywheel system to stabilize.

9. Check the vacuum level. The leaks have been repaired if the vacuum is within the specified range. A leak may exist in the system or an oil change is required if the vacuum does not pull down to the operating level. Proceed to ""DEADHEAD THE PUMP IF A LEAK IS NOT FOUND." ".

   Note: Continue leak detection in order to check for additional leaks. Change the oil again if a leak is not found. You may need to change the oil up to three times in order to qualify the vacuum. Continue checking for leaks if the vacuum does not pull down to the 25 mTorr operating level. Proceed to deadhead the pump if a leak is not found.

   ReferenceRefer to the Special Instruction, REHS7314-00, "Procedure for Testing the Vacuum Pump On Certain Uninterruptible Power Supply", for more information.

   Note: To ensure that all the oil is out if the pump, it will be necessary to tilt the pump during the oil change. Tilting the pump will also help insure all particulates are removed from the pump and the oil.

CHANGE THE OIL AND PURGE THE VACUUM

1. Verify that the system is in the "Bypass" mode.

2. For purging air from the pump:

   1. Turn the selector knob to the high flow on position "II".

   2. Turn the selector knob to low flow on position "I".

   3. Operate the pump until the oil is clear.

   4. Operate the pump for 10 - 15 minutes up to 30 minutes. You are looking for the vacuum level to stabilize with the ballast open (position "ll") and begin to draw the vacuum back down slightly.

   5. Do not stop operating the pump until the vacuum is in the operating level.

3. Check for contamination of the oil.

   Note: The sight glass may have a stain. A sight glass with a stain can give an appearance of containing contaminated oil.

4. Turn the selector knob to position "O".

5. Allow the vacuum to stabilize for a minimum of 1 hour up to 3 hours. A minimum of 6 hours is required in order to stabilize a dual flywheel system.

6. If bubbles and discoloration persist, then perform the Oil Change procedure again and go to step 2 for purging.

DEADHEAD THE PUMP IF A LEAK IS NOT FOUND

ReferenceRefer to the Special Instruction, REHS7314-00, "Procedure for Testing the Vacuum Pump On Certain Uninterruptible Power Supply".

Note: If the oil has not been changed prior to performing the Deadhead procedure the proceed to "Change the Oil in the Vacuum Pump" Section.

Note: The pump will not pull down to an acceptable level during the procedure if the interior seal has dried or the seal is worn.

1. Install the 295-5408 Sensor Kit on the pump.

2. Allow the pump to pull for 30 seconds. The pump is considered good if it pulls 5 mTorr or less. If the pump pulls between 5 mTorr and 20 mTorr it could indicate poor oil conditions. If vacuum pulls 5 mTorror less, reconnect and continue to check the system for leaks.

3. Drain the oil and replace the oil if the pump fails to pull 5 mTorr or less.

   1. Fill the pump with oil and run the pump for 30 minutes.

   2. Purge the pump for 10 - 15 minutes.

   3. Check the level of the vacuum pump. Proceed to Step 7 if the pump pulls below 5 mTorr.

   4. The pump is considered faulty and the pump should be replaced if the level is still above 10 mTorr. Continue to check for leaks in the system until the new pump has arrived.

4. Perform the procedure to deadhead the new pump in order to ensure that a faulty pump is not installed.

5. Install the new pump.

6. Check the vacuum in order to verify that the vacuum has dropped to an operating level below 25 mTorr.

   1. Air will be pulled into the system because of the time it takes to change out the vacuum pump.

   2. After the pump has been changed and the vacuum has stabilized the ballast should be set to "0" position for 5-10 minutes. This basically is pulling a vacuum to a stable level.

   3. Open the ballast to position "II", the vacuum will rise slightly.

   4. Once the vacuum stabilizes with the ballast in position "II" and begins to bring the vacuum level back down, then close the ballast to the "0" position.

      Note: If the vacuum pump has taken in considerable air or moisture, the technician will likely see white smoke (vapor) coming out from under the UPS at the end of the exhaust hose when the ballast is opened. This is normal and will taper off as the air/moisture is removed from the system.

7. Place the flywheel in the "ONLINE" mode.

8. Verify that the vacuum has dropped to an operating level below 25 mTorr.

9. Allow the vacuum to stabilize for a minimum of 3 hours. A minimum of 6 hours is required for a dual flywheel system to stabilize.

Note: The leak has been repaired if the vacuum is within the operating level. Repeat the leak checking procedures if the vacuum does not pull down to the operating level.

REPAIR A LEAK IN THE ARMATURE

Parts Required: 378-8315 Seal Kit

Note: Use 100% Silicon Sealer in order to repair the leak.

Note: If Bushings are not installed on all pins, then add them to the Armature pins without them.

Note: Be sure to brake the flywheel, so it comes to a complete stop. Then place the UPS in Bypass. After 5 minutes time, verify the UPS is de-energized, then proceed with the troubleshooting procedure.

Show/hide table



Illustration 1	g02351416
Bushing, Armature seal

Show/hide table



Illustration 2	g02351417
Split washer Flat washer Nut, Hex Connector, Armature terminal Bolt, Cap, Hex

1. Disconnect the terminal from the Armature copper pin.

Show/hide table



Illustration 3	g03041436

2. Clean the Surface of the armature pin and flywheel housing using Methanol or 99% Isopropyl alcohol.

   Note: A clean surface is essential for the silicone, in the next step, to create a lasting seal between the flywheel housing and the armature pin and bushing.

3. Apply GE Silicone Type II to the surface of the Bushing, Armature Seal, and into the Armature copper pin port of the bushing.

4. Apply the Bushing, Armature Seal over the Armature copper pin and up against the flywheel housing.

5. Ensure that the silicone extrudes around the bushing and through the bushing, around the Armature copper pin. Refer to Illustration 4.

Show/hide table



Illustration 4	g02354676
Extruded Silicone when Bushing, Armature Seal installed with 100% Silicone

6. Remove the excess silicone from the copper pin of the armature.

7. Clean the Armature copper pin using Methanol or 91% or greater Isopropyl alcohol.

8. Inspect the Bushing, Seal Armature to ensure that the silicone is still 100% around the Armature copper pin and the base of the Bushing, Armature Seal.

9. Slide Connector, Armature Terminal over the Armature copper pin to hold the Bushing, Armature Seal into place.

10. Use Washer, Flat on the bolt side of the Bolt, Cap and the Washer, Flat, Split and the Nut, Hex to secure the Armature cable to the Connector, Armature Terminal.

11. Wait for 1 hour in order to ensure that the vacuum is still in the operating range. Wiggle the cable gently in order to ensure that the leak has been sealed.

12. The leak has been sealed if the epoxy has cured and the vacuum is in the operating range after 2 hours.

REPAIR A LEAK ON THE POSTS FOR THE FIELD COILS

Note: Use 100% Silicon Sealer in order to repair the leak.

Show/hide table



Illustration 5	g01858373
Possible locations for a leak

1. Isolate the exact area of the leak on the post for the field coil. Use a syringe for the best results.

2. Fill the syringe with a silicon sealant.

3. Apply a moderate coat of sealant to the area of the leak. Apply the sealant to the area around the leak. The vacuum should drop immediately after the sealant is applied.

4. Smooth the sealant on the post.

5. Wait for 1 hour in order to ensure that the vacuum is still in the operating range.

6. Repeat the process until the vacuum remains in the operating range.

7. The leak has been sealed if the sealant has cured and the vacuum is in the operating range after 2 hours.

CONTACT CATERPILLAR.

Contact your dealership for a possible consultation with Caterpillar if a leak is not found and the vacuum continues to operate out of the tolerance level. Also, call if you have any questions that pertain to this procedure.

Specifications and Guidelines for Storage

Note: Do not operate a vacuum pump that has exceeded the specifications for storage. Do not operate a vacuum pump that has exceeded the operational environmental specifications. The vacuum pump must be replaced if the specifications have been exceeded. The replacement cost of the vacuum pump is not a warrantable cost.

The vacuum pump has the following specifications for normal operating temperature range:

Minimum temperature ... 0° C (32.0° F)

Maximum temperature ... 40° C (104.0° F)

The vacuum pump has the following specification on humidity for normal operation:

Minimum humidity that is non-condensable ... 5%

Maximum humidity that is non-condensable ... 95%

Temporary storage - storage that is no longer than 2 months

The vacuum pump has the following specifications on temperature for temporary storage:

Minimum temperature ... −25° C (−13.0° F)

Maximum temperature ... 70° C (158.0° F)

The vacuum pump has the following specifications on humidity for temporary storage:

Minimum humidity that is non-condensable ... 65%

Maximum humidity that is non-condensable ... 95%

Extended storage - storage that is between three and twelve months

Change the oil in the vacuum pump if the system has been stored for a length of time that is longer than a year. Energize the pump after the oil has been changed. Operate the pump for 4 hours. Operation of the pump will ensure proper lubrication of the seals.

The vacuum pump has the following specification on temperature for extended storage:

Minimum temperature ... 0° C (32.0° F)

Maximum temperature ... 40° C (104.0° F)

The vacuum pump has the following specification on humidity for extended storage:

Minimum humidity that is non-condensable ... 5%

Maximum humidity that is non-condensable ... 95%