Consolidation Testing – Equipment Maintenance Part 5 – Replacing the PCB Board Rechargeable Battery.

These ‘Equipment Maintenance’ posts are intended to show how to service and perform basic maintenance of different VJ Tech equipment used for consolidation testing. This post describes how to remove, check and replace the battery on a PCB. This may be when the battery has failed or following a prolonged period where the instrument has been switched off in humid conditions and will not power up.

Removing the PCB

The following picture shows the tools required to carry out this task.

Three of these tools may not be readily available, but can be ordered from Farnell electronics. The relevant numbers are;

Solder – 419-308

Solder Sucker – 179-2724

Solder Cleaning Wick – 252 - 499

IT’S IMPORTANT TO PLUG IN THE ANTI-STATIC WRIST BAND AND WEAR ON THE WRIST WHEN CARRYING OUT THIS TASK. ENSURE THE MACHINE IS POWERED DOWN.

Removing the PCB from the Instrument

Remove the front panel of the Control Box from the Instrument by unscrewing the retaining screws using the Large Posidrive Screwdriver as shown. Take care as there will be 3 connectors between the PCB and the Front Panel that need to be removed.

Remove the 3 connectors from the PCB (noting their positions for re-assembly), so that the Front Panel can be removed.

IMAGE

Checking Battery after 24 hours charge

Check the battery voltage with a multimeter. The voltage should be between 3.3V and 4V.

If the battery reading is not between these values and has not been replaced, it will need replacing as described in the following sections

Place the Front Panel to one side. Unscrew the Back Panel by unscrewing the retaining screws using the Large Posidrive Screwdriver.

Slide out the main internal unit.

Remove the PCB from its back plate by removing the retaining screws.

Remove any other connectors to the PCB (noting their positions for re-assembly).

Checking Track Damage Due to Battery Leak

First of all, identify the battery (1^st picture). Check the area around the battery at position B1 (as shown in the 2 ^nd picture) for any damage to tracks around the battery. Usually there will be white powder evident if the battery has leaked. If there is evidence of battery leakage, the PCB board will need to be replaced because the acid will probably have damaged the tracks. Please contact VJ Tech.

Removing the Battery

Heat up the soldering iron a high value (about 480°C).

There are two ways to remove the battery; the preferred method is Option 2.

Option 1
Using the soldering iron add more solder to battery terminals and then remove.

Option 2
On the component side of the PCB hold the battery.

On the reverse side of the PCB, alternately apply the soldering iron to the solder holding the battery legs whilst gradually removing the battery. The battery and legs should be removed in one complete piece after a short while.

Cleaning Up

Use the solder sucker and soldering iron to remove the majority of the remaining solder from the battery leg positions.

Clean up any remaining solder using the soldering iron and Solder Cleaning Wick.

Replacing the New Battery

Insert the new battery and solder in place, ensuring that the +ve side is in the correct position.

Re-assemble the instrument in the reverse order described above.

The machine should now power up normally and is ready for consolidation testing; if not, please contact VJ Tech.

Please take a look at our other blogs for more information on maintenance for our consolidation testing equipment.