Why does battery charger blink twice no matter where its plugged in?

If you use a fast charger, or a power charger, that can be the cause of your trouble. I used to charge with different power chargers till I learned they push every battery over its limits. After at least 3 different power chargers and about 100 defective batteries, I now charge my batteries with normal slow chargers. Before I can go on a shoot, sometimes 8 slow chargers are charging a whole night. But since I stopped using the power chargers I never lost a battery on overcharging (actually overheating)

do you live in a cold region? batteries or the charging pack wont charge when cold and often display rapid red blinks

Could be a bad battery. Check it with a different battery

please see the commentary. God bless you

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  The majority of laptops will display a solid green, blue or purple battery light to indicate that the battery is fully charged. Most manufacturers indicate that a laptop is in the process of charging by displaying a solid or blinking green, orange, blue or purple light. If your battery indicator light is green, blue or purple, the battery is probably functional, regardless of whether the light is blinking. If the light is solid orange, the laptop is probably in the process of charging.
  
  

Battery Error Coneventions

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  Many battery manufacturers use rapidly blinking lights to indicate that a battery's charge level is low. In general, a laptop will rapidly blink orange or red when its charge drops below a certain level until the computer is plugged into a power outlet and charged. If your laptop's battery indicator continues to blink rapidly in orange or red or if it remains red even when it is plugged into the charger, it indicates a problem with your battery or the charger.
  
  

Read more: http://www.ehow.com/info_12183593_blinking-battery-light-laptop-mean-charger-not-charging.html#ixzz2fu5qhEWg

please read and execute the commentaries. God bless you
Charging Conventions

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  The majority of laptops will display a solid green, blue or purple battery light to indicate that the battery is fully charged. Most manufacturers indicate that a laptop is in the process of charging by displaying a solid or blinking green, orange, blue or purple light. If your battery indicator light is green, blue or purple, the battery is probably functional, regardless of whether the light is blinking. If the light is solid orange, the laptop is probably in the process of charging.
  
  

Battery Error Coneventions

• 
  Many battery manufacturers use rapidly blinking lights to indicate that a battery's charge level is low. In general, a laptop will rapidly blink orange or red when its charge drops below a certain level until the computer is plugged into a power outlet and charged. If your laptop's battery indicator continues to blink rapidly in orange or red or if it remains red even when it is plugged into the charger, it indicates a problem with your battery or the charger.
  
  

Blinking can be a sign of an old or shorted battery, dirty contacts, poor connection with the charger, or a battery that has been drained too low.
First, clean your battery contacts on the radio, battery and charger with a pencil eraser. Try again to charge the battery. (Be certain the radio is turned off while on the charger.)
If this does not solve the problem, try a known good battery from another radio and see if swapping batteries solves the problem. If so, replace your batteries.
If the charger blinks no matter which radio you place on the charger, you may have a problem with one of the charge contacts in the charging tray itself. Once again, process of elimination will determine which one is the culprit. Then replace the bad charger.
The batteries will have a 2 year life expectancy, and there is a date code on the battery. It is either a 3- or 4-digit number. First number of a 3-digit code is the year, followed by the week of the year. Example 324 would be 2013 the 24th week. Four digit codes are similar except the first two numbers are the year, example 1324 would be 2013 the 24th week.
Best regards.

Ok all mine had the same problem however problem has been solved! The power cord that plugs into the charger is a common cord you may have laying around the house. I switched the power cord to my charger and the dreaded blinking stopped! Its just a bad power cord to the charging unit! Hope this helps!

does the laptop work when it is plugged in? i have a couple dells with bad batteries and the battery light blinks because of it. but they work when plugged in. could be a bad charger too. see if someone you know has the same charger and try that one

it might be it might just be a fulty charger

If the battery gets warm after being in the charger a while and still is not charged, then the battery is bad
if the battery stays cool in the charger then the charger may be bad
Chargers usually have a light code, I.E. on means charged, slow flashing means charging, and a quick blinking means bad battery
Some chargers have 3 lights and the code should be imprinted on the charger.
hope this was helpful, cb