APC Back-UPS Pro 900 battery refresh

Reading Time: 4 minutes

(applies to the BR900GI model as well as other in the range, 550GI, 1200GI & 1500GI)

Here is a writeup on how to recondition your UPS with cheaper standalone batteries rather than simply buying the manufacturers replacement pack.

My UPS is the APC Back-UPS Pro 900. I’ve had it about 10 years so well overdue a refresh of the internal batteries. I use the device to protect my Synology NAS as well as the local network and Internet access equipment from short power outages.

Recently, I needed to turn off the downstairs power sockets for 5-10 minutes. Given the age of the batteries they could not carry the load, even for that short period.

Process to replace UPS batteries

With the UPS on its side, open the slide cover at the bottom to reveal the battery compartment.
(Hopefully, your batteries haven’t leaked like mine!)

open cover showing original batteries
open cover showing original batteries

Remove / unpeel the green and red stickers from each side of the battery pack.
Be careful! You will need these again.

Original batteries with stickers removed and adapter plate
Original batteries with stickers removed and adapter plate

Remove the spade connectors from the old batteries. Be careful if yours have leaked as mine had and wear gloves to protect your skin.
(optionally) Clean up the spade connections as necessary to ensure good contact on the new batteries, be careful not to damage the protective insulation around the connections.

Connect the new batteries cross wiring them in series as colour coded by the cross over wire going from red (positive) on the first battery to black (negative) on the second battery.
(I found it much easier to do this with the batteries stood on their end vertically)

New batteries being connected by colour coded leads
New batteries being connected by colour coded leads

Re-attach the green and red stickers. Note the orientation of the connection to the UPS internally.
(Again, this is easier done first time with the unit stacked vertically as per the photo)

New batteries with original sticker to hold them together
New batteries with original sticker to hold them together

Before replacing the new battery pack it’s a good idea to “reset” the UPS.
Do this with the unit disconnected from the wall and with the internal battery out.
Press and hold the “On” button for 5 seconds to fully discharge the unit.
After the reset, with the stickers on, re-install the batteries into the UPS and replace the cover.
Plug in the unit and let it charge to 100% ready for calibration.

Calibrate new battery runtime

To get a more accurate “time remaining” figure from your UPS, it is best to manually calibrate the UPS once new batteries are fitted.

Manual calibration process

Make sure the battery is 100% charged.

Apply a constant load to the UPS of about 30% for the duration of the entire calibration.

(In a modern low power world this is not as easy as you might think. Classic none energy saving lightbulbs in desk lamps are a good bet to make ~100w but almost everything else these days is low power. Heating products like hair dryers are too much. Do not use equipment that will be damaged by sudden power loss as you will run the UPS till depleted.)

With sufficient load applied, disconnect the UPS from any USB / LAN control source and the mains power. Record the start time

Let the UPS fully discharge and shut down. Note the time.

Once complete recharge the UPS while switched off and without attached load.
After plugging in the UPS to mains power simply press the off button and leave for 12 hours

Turn on the UP and connect equipment to be protected, the runtime remaining should now be an accurate reflection of the load.

Sourcing compatible replacement batteries.

First, you need to work out what power rating your UPS has and how many individual batteries you require. Do this by opening the unit up and seeing what you already have.

For the APC Back-Pro series they have two batteries wired together via an interface plate. Power rating goes up with the model number.

Yuasa batteries from Japan have a good reputation and work well in my experience, they even have a UPS battery finder on their UK website for UPS compatibility.

I found HardwareExpress in the UK particularly helpful and super fast delivery. They do a “pack” for the Back-UPS Pro 900 here:

Using their UPS finder I instead went for slightly larger amp-hour capacity (8.5 Ah vs 7 Ah) but also £10 more at the time of this article.

New replacement batteries
New replacement batteries

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Ford automatic door locking via Forscan (MK3 Focus)

Reading Time: 2 minutes

If you want to enable automatic door locking when setting off on your Ford then I have written up the steps required from my own experience.

This is mostly so I can refer here in the future if I need to re-enable it.
Personally I find lists of steps better than a video where you have to go at the speed of the person making the video rather than quickly scanning down the list.

Tested on a UK spec vehicle. (MK 3 Focus & MK 7 Fiesta)

We all make our own choices. Make sure yours are the right ones for you

You will need

Make sure Forscan is installed, setup (not demo mode) and you have a license.

The process

  1. Turn the vehicle ignition ON (do not start, foot off clutch)
  2. Connect to the vehicle, wait for all the modules to be read
  3. Click “configuration and programming” (6 down)
  4. Select “BCMii Central Configuration (main)”
  5. Click play (bottom left)
  6. Read and understand the warning
  7. Click “OK”
  8. Wait for the process to run, turn ignition off when requested
  9. Change “mode” from “normal” to “engineering 1” (top left)
  10. Make a backup of the current settings by clicking “Save” button (bottom toolbar)
  11. Select “Automatic locking by speed” from the list of options
  12. Click “edit selected” button (bottom toolbar)
  13. In the pop-up select “02 – Automatic Locking”, then confirm with the tick
  14. Click “Write” button (bottom toolbar)
  15. Confirm the pop-up with the tick
  16. Follow the prompt to turn the ignition back on
  17. Read and understand the warning again
  18. Click “OK”
  19. “Block(s) programmed successfully” should be displayed along with a message to cycle ignition. Do this then click “OK”
  20. Stop Forscan by clicking the stop button (bottom toolbar)

Clear DTC fault codes

Due to the way the update is processed and written to the car BCM you will get a number of fault codes shown.  These can be cleared using Forscan

  • Enter DTC
  • Select Module with code
  • At the bottom, 2nd from the left click “Reset DTC”, confirm “Yes” on pop-up
  • Follow on screen instructions to cycle the ignition

First Time Setup

  • Go to https://forscan.org/ download & install
  • Once installed go to settings, uncheck “demo mode”
  • Register on the Forscan.org forum
  • Register for the 2 month free extended license http://forscan.org/forum/extlic.php
  • Better yet, support the development buy a full license from download page https://forscan.org/download.html
  • Follow the steps from the forum to copy the hardware id from your installed version of Forscan into the request on the Forscan forum extended license generator
  • One you have the license import it and start forscan for the first time, follow the instructions given for the setup of switch positions on the ELM327 lead / odblink and the ignition
  • Forscan will look at your vehicle and detect the settings, modules and any system faults.
  • Once setup is complete you are free to perform your chosen update / modification
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