Or, “Why Did My Dash Cam Suddenly Stop Working?!”
Security cameras include not only dashboard cameras like the ones we review on this site, but also home surveillance cameras, body cams for police officers, and others. If not connected to a closed circuit (CCTV), most security cameras will use a secure digital card, or SD card in short, to store the video footage recorded.
Most security cameras will work fine (for a while) with any class 10 microSD card. You can use either regular or High Endurance cards. Regular cards are cheaper, but due to the fact that security cameras record continuously for long periods of time — often even 24/7 — regular SD cards tend to fail you after a couple of months.
Some manufacturers include an SD card with the camera, specifically to avoid that their customers buy a cheap memory card and then become frustrated when their camera stops recording after a short while.
If your camera doesn’t come with an SD card, you want to make sure you get a High Endurance card that’s specifically designed for video monitoring. Here’s a relatively cheap suggestion:
SanDisk 64GB High Endurance Video Monitoring Card
- Class 10
- Up to 10,000 hours recording (that’s over a year of non-stop use)
In case you have an older camera that doesn’t support 64GB cards, this card is also available with 32GB capacity. Be aware that an SD cards’ expected life span is proportional to its capacity though, so a 32GB card will on average only last half as long as a 64GB card. The reason is that larger cards need to endure a lower number writing cycles over a given period of time.
As a result, larger cards are always better, and will last you longer. Ideally you would use the largest card that your camera supports. In 2018, most dashboard cameras support at least 64GB, and many will also take 128GB cards or higher.
For maximum durability, we therefore recommend getting a 128GB card, provided your camera (and your wallet) will support it. Here’s a couple of examples:
Samsung 128GB Pro Endurance Micro SDXC Card
- Class 10 / UHS-1
- Maximum write speed: 30 MB/s
- Supports Full HD (1080p) and 4K recording
- Up to 43,800 hours (1825 days)
Transcend 128GB High Endurance Card (Expensive)
- Class 10 / UHS-1
- Maximum write speed: 50 MB/s
- Designed for Full HD (1080p) video recording
- Up to 24,000 hours (that’s 1000 days straight)
Some Technical Background
Video surveillance cameras, typically write to the SD card continuously for long periods of time. In case of a dash cam, if you drive a lot, your camera may be writing to the memory card for several hours a day, or even 24/7 if you use parking mode.
Not all memory cards are designed to withstand this type of heavy use.
There are several types of SD memory cards, the most common ones being TLC (Triple Level Cell) and MLC (Multi Level Cell). SD cards employ flash memory, which in turn is made up of cells. In TLC cards, each cell stores 3 bits, whereas in MLC cards, each cell can hold only 2 bits.
Now TLC cards are cheaper to produce, which is why they are the most popular, but they also have a considerably lower lifespan. TLC cards typically endure 3,000 to 5,000 write cycles per cell, while MLC cards last for around 10,000 cycles.
There are other types of flash memory as well, such as SLC (Single Level Cell), with just one bit per cell. SLC is even more expensive though, and often only available in small capacities. SLC is typically used in industrial environments and for heavy-load servers.
For use in dash cams and other video surveillance cameras, High Endurance SD cards are ideal. These usually employ MLC technology. There’s more to it, such as the controller on the card that makes sure that all the cells are used evenly, but we don’t want to become too technical here as the article would become too long.
Just remember that video surveillance takes a heavier toll on a memory card than for example using it as extra memory for your phone, and make sure you get a High Endurance card for your dash cam.