UPS3 features misunderstanding

Post Reply
livecocoon
Posts: 1
Joined: Thu Oct 11, 2018 9:51 pm
languages_spoken: english
ODROIDs: Odroid C2
Has thanked: 0
Been thanked: 0
Contact:

UPS3 features misunderstanding

Post by livecocoon »

Hello,

I’m interested in your UPS3 system for Odroid motherboard in order to secure the system during power failure.
I’ve read your wiki and some explanations are not clear for me (my questions in bullet points)

- “Because of LiPo chemical characteristics, Battery Level can go little high when the load is quite light.
If your device reboot after shutdown, you should add a more delay after low battery alarm.”

o What do you consider as the load? The odroid + usb peripherals?
o How do you consider the reboot? Manual or automatic?
o Finally I don’t understand the link between the 2 sentences. Could you explain another way or with an example?

- Time to power-off at the Load
Current Time to power-off No Load Output voltage Output voltage at the Load VBAT
2A 25sec 4.97V 4.65V 4.14 V
1.8A 140s 4.69V 4.12 V
1.6A 450s 4.71 4.05V
1.4A 810s 4.73V 3.98V
1.2A 1470s 4.81V 3.95V
If your C2 takes 800mA and USB devices take 850mA, the UPS3 can supply the power to your system around 3~4 minutes at least.
It seems to be fine to shutdown the system safely.

o Regarding the table, the time to power-off is 450 seconds (or 7,5 minutes) if the delivered current is 1600mA. In the sentence below the table, you say that if C2 takes 800mA and USB devices 850mA so a total of 1600mA, the UPS3 can supply 3 to 4 minutes => half of 7,5 minutes calculated before. Could you explain me the trick?

ruppi
Posts: 258
Joined: Fri Feb 22, 2013 11:13 pm
languages_spoken: korean
Location: South Korea
Has thanked: 0
Been thanked: 36 times
Contact:

Re: UPS3 features misunderstanding

Post by ruppi »

Hi,

o What do you consider as the load? The odroid + usb peripherals?
I am not sure what the purpose of the question is, I request specific questions.

o How do you consider the reboot? Manual or automatic?
If the battery voltage reaches 3.7 volts or more after power is cycled, it will automatically boot.

o Finally I don’t understand the link between the 2 sentences. Could you explain another way or with an example?
If there is a large flow of load, the predicted time is the worst assumption since the actual battery voltage would also be switched off earlier than expected if the voltage would be significantly lowered.


BR,
Ruppi

Post Reply

Return to “UPS”

Who is online

Users browsing this forum: No registered users and 2 guests