Forum Home
PC World Chat
 
Thread ID: 88095 2008-03-15 05:30:00 How do Digital Camera keep their RTClock when batteries die. John W (523) PC World Chat
Post ID Timestamp Content User
649590 2008-03-15 05:30:00 My wife possed thes query to me and Im stumped for an answer.

The Real Time Clock keeps current date even if the camera is left with dead batteries after a few weeks or month.

Thanks

John in Mosgiel.
John W (523)
649591 2008-03-15 06:02:00 My camera has a second, button-cell battery for keeping the clock current. My guess is that most cameras simply make this a non user-replacable part, and require opening the camera to change it. Erayd (23)
649592 2008-03-15 06:02:00 Often they have another separate button cell battery just for the clock. What camera? PaulD (232)
649593 2008-03-15 06:04:00 Two possible reasons:
1) Dead batteries may not be as dead as you thought. The camera does not require substantial amount of power to maintain the inner "clock".

2) There is a backup battery. On my old film-based camera, there is a CR2032 cell located on the cover of the device which is responsible for keeping the time.

Cheers :)
Renmoo (66)
649594 2008-03-15 06:22:00 Ho John. Not a silly question from your other half. I regularly shuck the batteries from two cameras to recharge them and, I must admit, I had not given a thought to the time retention..... nice one. :) Scouse (83)
649595 2008-03-15 08:14:00 As has been said, the clock uses almost nothing. The same is the case in a VCR clock and as I'm aware they use a slow release capacitor. When you disconnect then reconnect the power, the VCR retains the clock and programme information. Perhaps the camera also has a slow release capacitor? Roscoe (6288)
649596 2008-03-15 08:32:00 I'm sure my Panasonic Lumix has a Supercap to keep the clock running but I have just re-read the manual and cannot find any mention of it. decibel (11645)
649597 2008-03-15 09:24:00 The Panasonic FZ-30 manual states that so long as a fully charged battery has been in the camera for more than 24hrs the clock will keep going for 3 months. PaulD (232)
649598 2008-03-15 09:31:00 The Panasonic FZ-30 manual states that so long as a fully charged battery has been in the camera for more than 24hrs the clock will keep going for 3 months.

Sounds as though the (very) slow release capacitor requires 24 hours to charge.
Roscoe (6288)
649599 2008-03-15 11:51:00 A watch can run for years on a button cell and yet we still have to reset the time on microwaves, ovens, alarm clocks and the like if power fails for even a second. It's good to see an example of something that actually just works for this. TGoddard (7263)
1 2