MrBin

Hi everybody!
I changed the battery of PLC S7-400. In product information, guiding:
Before you change a buffer battery you have to depassivate it. Proceed as follows:
1. Set the switch Batt Indic to Off.
2. Remove the old battery/ batteries.
3. Depassivate the new battery/ batteries by short circuiting the poles for 1 to 3 seconds.
4. Insert the new battery/ batteries.
5. Set the switch Batt Indic to 1 Batt or 2 Batt.
A battery fault will now only be displayed, if you inserted an empty battery.
I don't understand item "3. Depassivate the new battery/ batteries by short circuiting the poles for 1 to 3 seconds."
Hope about your help!
Thanks!

 Above instructions are very nice.

But two questions from my side:

At battery changing time CPU power supply will be OFF or ON?

Approximately Batter life time ?

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Split from Changing a battery of PLC S7-400..

Hello Dear Ballsandip

1. During the replacement of the battery, nothing will happen to the power supply. And it remains power on

2. If the power supply is off and only the batteries prevent memory clearance. It will then take about a month for the batteries to discharge.

ballsandip

 

MrBin

Hi everybody!
I changed the battery of PLC S7-400. In product information, guiding:
Before you change a buffer battery you have to depassivate it. Proceed as follows:
1. Set the switch Batt Indic to Off.
2. Remove the old battery/ batteries.
3. Depassivate the new battery/ batteries by short circuiting the poles for 1 to 3 seconds.
4. Insert the new battery/ batteries.
5. Set the switch Batt Indic to 1 Batt or 2 Batt.
A battery fault will now only be displayed, if you inserted an empty battery.
I don't understand item "3. Depassivate the new battery/ batteries by short circuiting the poles for 1 to 3 seconds."
Hope about your help!
Thanks!

 Above instructions are very nice.

But two questions from my side:

At battery changing time CPU power supply will be OFF or ON?

Approximately Batter life time ?

------------------------------------------------------------------------------------------
Split from Changing a battery of PLC S7-400..

 Hello,

• Depassivate the new batteries by applying a short circuit to its poles for a short period (1-3 sec.) and then insert it in the Power supply.
• You can insert the new batteries in the Power Supply while it's On.
• Battery life depends on the modules on the rack.
  For each module on the rack find the value of "backup current" and calculate the sum of it.
  And then calculate the time as per example in the following link: 
  How great is the power requirement (from the backup battery) of the modules to be backed up at "Power Off" and what is the relationship between the backup current and the length of the backup time?

Hope this helps.