AERONET Instrument Troubleshooting Interface - Solutions for CIMEL EXTERNAL BATTERY NEGATIVE TREND Flag

Description
The instrument draws power from an external 12 V battery . This flag is raised when the daily average battery voltage shows a declining trend over the past month that exceeds a defined slope threshold, suggesting the battery is losing capacity or connections have degraded. A slow downward trend is typically due to aging or oxidized terminals rather than a sudden failure.

Condition(s)
Include battery voltage trends for all 3 batteries:
Scan daily average battery voltages for previous month; flag if the trend is less than -0.5V for DCP and Cimel External 12V batteries; flag if the trend is less than -0.2V for Cimel 6V internal battery

How To Check/Test
(See example)

Models 4 and 5: VIEW > BAT (disconnect solar panel before checking)
Model T: MEASURES > Battery (disconnect solar panel before checking)

Solution Level 1 (< 5 minutes)
1. Check/reseat all connections between solar panel and control box.
2. Check/reseat connector panel.
3. Check/reseat connections going to external battery.

Solution Level 2 (more involved)
Models 4 and 5:
1. Check/reseat internal connections and check TIP32 transistor for burning. (See Internal check control box and TIP32)
2. Check power coming directly from solar panel. (See Connector Panel Charging Voltage Test)

Version T:
1. Check power coming directly from solar panel (MEASURES > Vsolar, Isolar)

Solution Level 3 (last resort)
1. Replace battery or solar panel.
2. Return instrument for maintenance.