MFA150 Battery Replacement 1

[wallymcdoogle]

I need to replace 3 trays of 4 batteries which are attached to my MFA150.

There are 3ea MPR25.

There are currently 3 trays of 4 batteries each. 3ea 12V and 1ea 10V battery. I'm replacing these with 4ea 12V batteries based on a suggestion from a pro.

The instructions say to detach the charging lines from the back of the MFA150. Do you think there is a problem with detaching from the other end of the wire right from the battery distribution box? It simply has 1 large fuse per tray of 4 batteries. The back of the MFA150 is a tight area to work with hot leads. Any suggestion is appreciated.

Also, since I'm using 4ea 12V batteries instead of 3ea 12V plus the 1ea 10V as is currently, is there any calibrations that should be done?

Any other overall precautions I should take?

Thanks

Wally

 

[GHTROUT]

While there may be someone qualified here, I would only allow a battery expert to work on my battery plant. They do this all the time to all kinds of systems, and generally, nobody dies because of that.

Telecom vendors usually just sub this work out to battery companies because the frequency of the work is so low.

[©] GHTROUT.com [⇔] Resources for Nortel Meridian/CS1000 System Administrators - You Can Hire Me Too

 

[Jeffnortel]

I've had to do this plenty of times and I never disconnect the cables inside the mfa150.

You can change these out without it interupting the pbx.

Flip the switch on the panel of the mfa to bypass.

Disconnect from the batteries, tape the ends of the cable and replace the batts. Expect a small ark when you attach the leads from mfa on the new batts.

Hope this helps

 

[wallymcdoogle]

Thanks Jeff!

All done, though it was a pain! Not as strong as I used to be.

Wally

 

[Wane47]

You also have to adjust the float voltage of the rectifier for the batteries you installed. You need to find out from the manufactor of the batteries as to what that is. From the voltages that you listed. 12 volts and 10 volts, They were installed when nortel would not support you changing the float voltage, so vendors had a battery supplier furnish batteries that met nortel fixed float voltage (it was set for wet cell batteries). They removed one cell from a 12 volt battery to do that. that was on the older rectifiers, mfa 150's allowed you to change the float voltage. The wrong float voltage will shorten the life of the battery so I was told.

 

[telebub]

I agree with GHTROUT and WANE47. Last week we had our partner that we always use for battery testing and replacement come out to a customer and replace the batteries. They performed the replacement by installing a temporary battery string 1st then removing the old batteries. After installing the replacement batteries, they removed the temporary battery string and then adjusted the float voltage from around 52V up to 54V. The battery tech said if it stayed at 52V the batteries wouldn't charge properly and not last as long.

War Eagle!
Lions Baseball '09!