AERONET Instrument Troubleshooting Interface - Solutions for CIMEL CLOCK SHIFT Flag

Condition(s)
Flag if > 1 minute, list the date when it happened for the last time

How To Check/Test
Models 4 and 5: PW: 1 > DAT
Model T: DATE

Solution Level 1 (< 5 minutes)
Models 4 and 5: Correct clock to exact UTC time (set forward by 1 minute, then press OK as the master UTC clock hits :00). See Model 5 Set Cimel Date and Time document or Model 5 Set Cimel Clock video (AVI, MOV) - Instructions on modifying the Cimel control box time (transcript)

Version T: Correct clock to exact UTC time. (See Model T Set Date and Time)

Solution Level 2 (more involved)
If experiencing recurring clock shifts:

Models 4 and 5:
1. Ensure internal battery voltage is at least 5.0 V (VIEW > BAT - disconnect solar panel before checking).
2. Check/reseat internal connections and internal battery. (See Internal check control box)

Model T:
1. Ensure GPS coordinates are correct under the "Settings" menu.
2. Check/reseat GPS antenna. (See GPS connection)
3. Run GPS Synchronization. (See Model T GPS Synchronization)

Solution Level 3 (last resort)
Models 4 and 5:
1. If on AC power, ensure there are no spikes in AC voltage. Run instrument on battery power only if possible.
2. Return instrument for maintenance.

Model T:
1. With the power disconnected, open the control box and verify the GPS antenna is connected to the board. (See Model T Internal Connections)
2. Replace the GPS antenna.
3. Return instrument for maintenance.