
5 
LED condition: 
Switch on power and insert two HD in terms of different working pattern 
 
HDD carries on the self-checking 
HDD1 and HDD2 LED flashing 
simultaneously with blue light. 
Self- checking completes when 
HDD LED shows no light 
During Data transmission: The 
HDD1 and the HDD2 LED flashing 
simultaneously with blue light. The 
Data transmission completes when 
HDD1 and HDD2 LED flashing 
simultaneously with blue light. 
Self- checking completes when 
HDD LED shows no light 
During Data transmission: The 
HDD1 and the HDD2 LED flashing 
simultaneously with blue light. The 
Data transmission completes when 
LED shows no light 
First HDD1 LED start flashing blue, 
then HDD2 LED start flashing blue. 
Self- checking completes when 
HDD LED shows no light 
During Data transmission: 
HDD LED flashing with blue light. 
The Data transmission completes 
when LED shows no light 
First HDD1 LED start flashing blue, 
then HDD2 LED start flashing blue. 
Self- checking completes when 
HDD LED shows no light 
During Data transmission: The 
HDD1 LED is flashing blue till the 
HDD is full, then HDD 2 LED is start 
flashing. The Data transmission 
completes when LED shows no light 
 
After power on and insertion of one or two HD the following LED states appear after a 
HD failure. 
(In this example HDD1 is normal and HDD2 is damaged, otherwise vice versa) 
 
HDD carries on the self-checking 
Power 1 is constant blue and HDD1 
is flashing blue, Power 2 LED is off 
and HDD2 LED is constant blue. 
Selfchecking completes when the 
Power 1 LED is constant blue and 
HDD1 LED shows no light, 
Power 2 LED is off and HDD2 LED 
is constant blue. 
Under the Data transmission 
condition: The HDD1 LED flashing 
with blue light and the HDD2 LED is 
constant blue. The Data 
transmission completes when 
HDD1 LED shows no light and the 
HDD2 LED stay blue 
JBOD Under the Data transmission 
condition: The HDD1 LED flashing 
with blue light and the HDD2 LED is 
constant blue. The Data 
transmission completes when 
HDD1 LED shows no light and the 
HDD2 LED stay blue