KABAR Preventive Maintenance Procedure
This checklist outlines the preventive maintenance procedure for the KABAR equipment, detailing the steps and tasks necessary to ensure optimal performance.
KABAR Preventive Maintenance Procedure
This checklist outlines the preventive maintenance procedure for the KABAR equipment, detailing the steps and tasks necessary to ensure optimal performance.
Coordinate All Maintenance Work With The Production Supervisor
Record Power Setting, Plate Current, Minimum Grid Current and Frequency
To observe power level, plate current and grid current: a) If off, power up the machine b) Place 20-20 mil vinyl under bar for sealing c) Start seal process and note results
Power Setting
Plate Current
Minimum Grid Current
!!! Always follow our approved "Lockout/Tagout" procedures and use a high voltage grounding probe to discharge capacitors etc. before working in or near any high voltage area in the machine !!!
!!! Once set (at Kabar facility or with Kabar input if frequency found to be incorrect), the frequency should never need to be adjusted !!!
Output Frequency
To observe the output frequency (Use BK Precision 1805 80MHz freq. meter): a) If off, power up machine b) Plug in frequency counter and attach antenna c) Turn on and set to the following settings: FREQ. - MHz RESOLUTION - 100 HOLD - OFF FILTER - OFF ATTEN. - X1 NOTE OBSERVED FREQUENCY (FREQUENCY TO BE 27.12MHz)
if the answer is "noneOf [Yes]"
1) If on, power down machine 2) Lockout the machine per our "Logout/Tagout" procedures 3) Open cabinet door 4) Use a grounding rod to short the grid trombone, B+, and all capacitors to ground 5) Locate frequency adjustment plate (see figure below) and mark current position 6) Loosen bolts to adjust plate position 7) Tighten bolts 8) Close cabinet door and power up machine 9) Check output frequency 10) Repeat as necessary
!!! The following tests should never be done alone! The mechanic must have help close by due to the dangerous voltages/currents present!!!
!!! Always use a high voltage grounding probe to discharge capacitors etc. before working in or near any high voltage area in the machine!!!
Check Tube Condition (Filament Voltage/Current At Filament Transformer, Bench Test)
Tools needed: - Flat and Phillips head screwdrivers - 5/16" - 11/32" - 3/8" - 7/16" - 1/2" Wrenches - Nutdrivers and 1/4" drive ratchet set recommended - Allen wrench set - Vacuum cleaner - Air hose with blow gun - Contact cleaner - Surface cleaner and rags
3CX5000H3 Specs (10KW Units)
- 7.5 Vac, +0, -5% (Min= 7.125 / Max= 7.5) - Plus 0, Minus 5% - Set transformer taps as needed - Record changes made
YU-108 Specs (4KW Units)
- 7.0 Vac, +0, -5% (Min=6.65 / Max= 7.0) - Plus 0, Minus 5% - Set transformer taps as needed - Record changes made
To Check Filament Voltage
a) If on, power down machine b) Lockout the machine per our "Lockout/Tagout" procedures c) Open cabinet door d) Use grounding rod to short grid trombone, B+, and all capacitors to ground e) Connect digital multimeter to the tube filament center tap and set meter to AC volts f) Power up machine and record voltage reading g) Power down machine, disconnect meter
Filament Voltage
!!! Lockout/Tagout machine for cleaning and physical inspection process !!!
To Check Filament Current
a) If on, power down machine b) Lockout the machine per our "Lockout/Tagout" procedures c) Open cabinet door d) Use grounding rod to short grid trombone, B+, and all capacitors to ground e) Clamp digital amp meter around positive filament lead f) Power up machine and record Amp reading g) Power down machine, disconnect meter
AMP Reading
NOTE: Newly built tubes run at approximately 73 - 78 Amps. As the current draw by the tube increases, its ability to efficiently emit RF drops. An increase in current draw indicates a limited life cycle.
To bench test tube (See Cleaning and Physical Inspection section below for tube removal process) a) Check resistance across the filament i) Resistance should be low b) Check resistance between filament and grid ring i) should be open c) Check resistance between grid ring and ground i) should be open
Cleaning And Physical Inspection
5) Disconnect leads to tube, note their position
Add or drag pictures
12) Inspect all wiring for insulation breakdown, loose connections, and any sign of overheating
13) Inspect all ceramic posts for cracks, replace as needed, clean posts with contact cleaner
!!! It is strongly recommended that the tube cleaning procedure (Step 13 above) be performed over a foam cushion, in the event that the tube is dropped!!!
14) Remove each relay (one at a time) and inspect for pitting and/or charring on the contacts
18) Check bolt holding platen and bar to air cylinder to ensure it is tight
Confirm Machine To Be Within Specifications
No Load Testing/Setup
i) Never activate RF without at least one layer of vinyl under the bar
Note Grid Current
If grid current is not 0.45A, adjust trombone to bring grid current to 0.45A
i) Power down machine ii) Lockout the machine per our "lockout/tagout" procedures iii) Move trombone bridge toward tube to lower grid current iv) Move trombone bridge away from tube to increase grid current
Load Testing
Note Plate Current
i) Begin with low turning dial position and work up until adequate weld is achieved ii) 1.5A minimum permitted plate current to be achieved
Note Grid Current
i) If grid current falls below 0.25A during RF cycle tube is falling (assuming no load test has been performed and no load setup verified) and should be replaced
Record Frequency, Power Setting, Highest Plate Current, and Lowest Grid Current
Frequency
Power Setting
Highest Plate Current
Lowest Grid Current
Changes Made:
Test The Arquench
9) Verify that arquench fires and aborts RF cycle (Plate and grid drop to 0)
14) Verify that arquench fires
NOTE: The arquench test is to verify the functionality of the arquench system. This system should be checked during a monthly PM check
Check Bar Levelness
Return Machine To Service
Readings:
Auxiliary Checks
Inspect solder gun
a) Inspect power leads and connectors for cracks, broken shell covering, excessive electrical tape repairs, etc., replace as necessary b) Inspect foot switch for proper and safe operation
Inspect turntable movement
a) Check for excessive drag, grease as necessary b) Lubricate all wheels and bearings
Source: Latham Pools - Suwanee (Community Member)