Denso 400BW-CE User Manual page 166

Charging Operation and LED Indication
Operator's Action
Place the BHT on the CU-400.
⇓
After approx. 3 hours
when the CU-401/421 is powered from the
A C adapter
⇓
Remove the BHT.
If the CU-421 is self-powered via the USB interface from the USB host (PC) or USB hub and the host PC
is in suspend mode, the CU-421 cannot charge the battery cartridge.
If the host PC switches to the suspend mode when the CU-421 is charging the battery cartridge, then the
CU-421 stops charging. When the host PC recovers from suspend mode, the CU-421 starts charging
again. To prevent the CU-421 from getting affected by suspend mode, use the dedicated AC adapter.
CU-400 Status
On standby
⇓
Charging
⇓
Charging completed
⇓
On standby
146
Charge LED on the BHT
OFF
ON
(in red)
ON
(in green)
OFF