Replacing an SRM battery... at home :o)

[MichaelK]

Standard 130BCD PM6 is also only a single EF651625, soldered to the PCB.

[uraz]

So it looks like PM6 has 1 battery and PM7 has 2 batteries regardless of BCD (cannondale hollowgram version).

[sqber]

The instructions I have seen all show how you must use soldering iron to first remove the wire from the old battery, cut the terminals of new battery and then solder the wires to the new battery. The battery I found today, already has a wire attached, but my question is - is the plug attached to this battery compatible with the female part on SRM power meter? If so, it is purely the matter of swapping, no soldering or cutting anything. Seems sweet.

Answer - NO, the attached wires don't fit the connection inside PM7. So I had to remove the attached wires from new and old batteries and soldered the wires from the old battery to the new battery.

[markc]

Howdy gang,

Following up on the connector discussion upthread for the next DIY'er who google searches. Here are the micro JST connectors with leads to use in SRM battery changes. Sourced these from Amazon (USA):

https://www.amazon.com/gp/product/B01DU ... UTF8&psc=1

Thanks to the folks upthread for the pointer to the micro JST connectors.

Also, my SiSl spider is a PM7 compact and has dual batteries. The expected rectangular LTC-7PN-S4 units.

--Mark

[Erwin]

Does someone know how to open a PM7 Origin spider? Here are some pictures. I have changed the batteries from a 9000 series, but here I don't know which part is the lid to open. Thank you all.
I think the bottom cover with the SRM label "SRM PM7" should be removable. But no real gap where I could lever with a tool or something.



Bottom lid should be correct. Here a picture from a PM9, the aluminium remains the same. Nevertheless actually I don't know how to remove the cover.

[mortirolo]

Does someone know how to open a PM7 Origin spider? Here are some pictures. I have changed the batteries from a 9000 series, but here I don't know which part is the lid to open. Thank you all.
I think the bottom cover with the SRM label "SRM PM7" should be removable. But no real gap where I could lever with a tool or something.



Bottom lid should be correct. Here a picture from a PM9, the aluminium remains the same. Nevertheless actually I don't know how to remove the cover.

+1

[mortirolo]

The plastic cover was hardly glued. It's not too safety I guess.

[ms6073]

The plastic cover was hardly glued. It's not too safety I guess.

The covers on most SRM powermeters are usually of the press-fit variety as I did not think they would evey be glued!

[pagnini]

Does someone know how to open a PM7 Origin spider? Here are some pictures. I have changed the batteries from a 9000 series, but here I don't know which part is the lid to open. Thank you all.
I think the bottom cover with the SRM label "SRM PM7" should be removable. But no real gap where I could lever with a tool or something.



Bottom lid should be correct. Here a picture from a PM9, the aluminium remains the same. Nevertheless actually I don't know how to remove the cover.

The back cover of the latest SRM PM7 or PM9 is not mounted on the body using screws and sealing ring like the older ones. It is glued using sealant. I have successfully removed it using some hot melt glue and a screw driver. Clean the surface of the cover near on one side carefully first, then heat one side of a hot melt glue and press it on the surface which has been cleaned. After the glue stick is hardened， try to pull the it and you can find the cover can be moved. If the pulling force is not large enough such that the glue stick is stripped off, you can try to use two sticks or change a bigger one. You can use the screw if the gap is big enough. Once if the battery is changed, you need to clean the residual of sealant and use new sealant to glue the cover again.
I have posted one picture of my PM7 back cover and you can see some residual of the hot melt glue clearly. Good luck:)

[greedy]

Hello. Water got into my SRM. Almost everything has been restored, but some elements have rotted and there is no way to set their nominal value. Maybe someone can measure the resistance of the resistors R14, R17, R28? Thank you in advance!