The BCDC Alpha range, including the 25A (BCDC12025B), 50A (BCDC12050B) and 50A-R (BCDC12050R) DC Battery Chargers, may display a flashing Float LED to indicate a fault condition.
This typically begins as a soft fault (Float LED flashing with the control button LED off), where the charger will still operate, but if the issue escalates it becomes a hard fault (Float LED flashing with the control button LED on), and charging will stop.
Common causes include low voltage alarms, auxiliary battery overvoltage, charger overvoltage, or charger overcurrent.
Diagnosis requires checking battery voltage, confirming the BCDC Alpha is the sole charging source, inspecting for voltage drop, and verifying wiring and fuse integrity.
While low voltage alarms often occur if the auxiliary battery is flat, overvoltage issues may stem from secondary charging sources like solar regulators or poor wiring. In rare cases, charger overcurrent may be the cause.
REDARC recommends seeking the support of a qualified auto electrician or technician.
Important
In this article we explain the need for testing to determine the cause of the issue. Testing may involve changes to the installation or wiring. For your safety and accuracy, REDARC recommends engaging a REDNetwork member or a suitably qualified auto electrician - Find Your Local Installer
This information is applicable to the following BCDC Alpha chargers:
- BCDC Alpha 25A DC Battery Charger (BCDC12025B)
- BCDC Alpha 50A DC Battery Charger (BCDC12050B)
- BCDC Alpha 50 R DC Battery Charger (BCDC12050R)
What does this look like?
The BCDC Alpha Float LED will flash when a soft fault is detected.
It can present as a soft fault initially and therefore the control button LED will be off. If the condition worsens, it will become a hard fault and the control button will turn on while the Float LED flashes.
What does the flashing float LED mean?
This fault indicates that the BCDC Alpha has detected conditions outside normal voltage range or the auxiliary battery voltage is lower than the set Low Voltage alarm settings via the App.
Will the BCDC Alpha still charge my battery in this condition?
If the control status LED is off (soft fault), the BCDC Alpha will continue to charge the auxiliary battery. If the control status LED is illuminated (hard fault), the BCDC Alpha will cease charging.
What can cause this fault mode?
This fault can be caused by one of the following conditions:
- Low voltage alarm
- Auxiliary battery overvoltage
- Charger overvoltage
- Charger overcurrent
How to determine the cause of the flashing float LED?
Below is a list of the common causes and repairs.
A) LOW VOLTAGE ALARM
This is a soft fault, indicating that your auxiliary battery is below the low voltage alarm configured via the RedVison configuration App. In this condition, being a soft fault, the Control Button LED will be off.
Things to check:
- Is the battery flat?
- Using a multimeter, measure the auxiliary battery voltage.
- If you measure below the low voltage alarm setting (default is 9V) it will cause this fault condition.
- Review cause of why the battery went flat.
- Recharge the battery.
- Re-check operation.
Note: Default setting is 9V and the settings are configurable between 8.0-15.0V. If it was in the default settings and voltage is below 9V, it will present this fault condition.
B) AUXILIARY BATTERY OVERVOLTAGE
This is a hard fault indicating your auxiliary battery is above the expected voltage. In this condition, being a hard fault, the Control Button LED will be on.
Things to check:
- Using a multimeter, measure the auxiliary battery voltage.
- Ensure the BCDC Alpha is the only charging source.
- Confirm the BCDC Alpha voltage by measuring the voltage between ground and auxiliary battery (B+) see diagram below.
Note: Secondary chargers (if used) such as an external solar regular could be the cause.
C) CHARGER OVERVOLTAGE
This is a hard fault indicating that the auxiliary battery terminal voltage is outside the voltage range. In this condition, being a hard fault, the Control Button LED will be on.
Things to check:
- Using a multimeter, measure the auxiliary battery voltage.
- Ensure the BCDC Alpha is the only charging source.
- Compare the BCDC Alpha voltage to the voltage measured at the auxiliary battery in step 1 by measuring the voltage between ground and auxiliary battery (B+) at the BCDC Alpha, see diagram above.
- If there is a difference in voltage present (voltage drop), this could contribute to the issue.
- Address voltage drop and re-check operation.
Note: Common causes of voltage drop are as follows:
- Undersized cable
- Poor connections - such as loose or damaged terminal/connections
- Faulty fuse protection
Note: Secondary chargers (if used) such as an external solar regular could be the cause.
D) CHARGER OVERCURRENT
If none of the above conditions are present, the last possibility is charger overcurrent.
Note: This is an extremely rare and unlikely condition.
Things to check:
- Ensure the BCDC Alpha has good power supply.
- Check all wiring connections.
- Repair any wiring issues such as loose or poor connections and faulty fuse protection.
- Re-check operation.
- If the issue persists, further specialist diagnosis is required.