- Uninterruptible Power Supply:
- UPSB505 (S/N: YTM1-UP)
Introduction
This Special Instruction contains information of new IGBT driver assembly that has been released to production to decrease the IGBT failure rate and limit the effects of an IGBT failure.
Do not perform any procedure in this Special Instruction until you have read this Special Instruction and you understand this information. Use only proper tools and observe all precautions that pertain to the use of those tools. Failure to follow these procedures can result in personal injury.
ReferenceTesting and Adjusting, UENR1799-00, "UPSB505 Uninterruptible Power Supply UPS Battery - 50Hz"
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, the user must ensure that it is safe for the user and for other people to use.
The user should 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.
 |
Power source must be disconnected before working on equipment. Failure to disconnect power source could result in injury or death. |
 |
|
High voltage may be present. The power source must be disconnected before working on the equipment. Failure to disconnect the power source could result in injury or death. Verify that the equipment is not energized before performing any maintenance. This work must be performed by trained personnel with correct tools and procedures. |
|
|
Personal injury or death can result from high voltage. Moisture can create paths of electrical conductivity. Make sure that the electrical system is OFF. Lock out the starting controls and tag the controls "DO NOT OPERATE". |
|
New IGBT Driver (DRV6T)
Redesign of the IGBT Sub-Assembly
 | |
| Illustration 1 | g03544976 |
Old Design of IGBT | |
 | |
| Illustration 2 | g03544980 |
New Design of IGBT | |
UPSB505 New Driver Architecture
The new driver architecture of UPSB505 are shown in the Illustration 3 and 4.
 | |
| Illustration 3 | g03551176 |
(1) New IGBT driver boards DRVxT + new snubber caps (2) New Ribbon Cable (3) New Ferrite for dry contact EMC protection | |
 | |
| Illustration 4 | g03551318 |
(4) New Firmware AQ mini (5) New INOUT Board (6) New Cable between INOUT and EXPUT Board (7) EXPUT rev JA mini | |
New EMC plate for 500KVA Integrated parallel only.
 | |
| Illustration 5 | g03551337 |
(8) EMC plate installed | |
IGBT Driver Comparison
The comparison between the current driver design and the new driver design is given in the following Table 1.
| 500 KVA Current Design | 500 KVA New Driver Design |
|---|---|
| MUTxT Boards | DRVXT Boards |
| Ribbon Cable Old Design | Ribbon Cable New Design |
| EXPUT (BA to HA) | EXPUT JA |
| INPUT Board | INOUT Board |
| Snubber Caps old design | Snubber Caps new mechanical design |
| Firmware AQ mini | |
| New EMC Plate for 500 KVA int | |
| New Ferrite |
New Part Numbers for UPSB505
New Part Numbers for UPSB505 UPS with new driver IGBT have been released. The new part numbers are given in the following Table 2.
| Quantity | Part Number | Description |
|---|---|---|
| 1 | 449-0277 | Rod |
| 1 | 449-2982 | Switch |
| 2 | 449-2983 | Switch |
| 6 | 449-2984 | Switch |
| 1 | 449-2985 | Circuit Board As |
| 1 | 449-2986 | Plate |
| 1 | 449-3371 | Cable As |
| 1 | 449-3372 | Cable As |
| 1 | 449-3412 | Suppressor |
Drivers Of IGBT
 | |
| Illustration 6 | g03546998 |
Each driver signifies a specific function, below Table 3 shows the drives with their function.
| Function | DRVxT Board | Quantity Per UPS |
|---|---|---|
| PFC | DRV6T | 9 |
| INV | DRV6T | 9 |
| CH | DRV4T | 6 |
| NL | DRV3T | 1 |
Starting a UPSB505 with new Driver IGBT
- MTEST are not required anymore as the LED'S are now implemented on the DRVxT Board.
- Minimum firmware revision required AQ, check the firmware revision before starting up the UPS and update if necessary.
- Check that the dry contacts wires are connected as described in the installation manual.
 | |
| Illustration 7 | g03547016 |
Note: The operator must pass the wire through the Ferrite two times.
Repair Procedure
- Open doors of UPSB505, Put the UPS in Maintenance Bypass as per Testing and Adjusting, UENR1799.
- Wait 5 minutes for the capacitors to discharge.
- Remove the front panel to access the IGBT module.
- Replace the defective part as per Testing and Adjusting, UENR1799.
- Replace the protective covers.
- Restart the UPS in manual mode
MTEST are not required as the LED's are now implemented on the DRV6T board.
 | |
| Illustration 8 | g03547318 |