EverFocus PowerPlex EDR1600 Administrator's Manual And Operating Instructions page 64

Note 1: HDD#2 being not accessible is caused by the misbehavior of
HDD#1 at hot-swap. (HDD#1 responds to all commands sent to
HDD#2 if the former "thinks" the later is absent!) We strongly
recommend that you use IBM's hard disks as HDD#1 (master) because
they are very consistent and stable for hot-swap.
Note 2: If it happens that HDD#2 is not accessible, please power off
both HDD#1 and HDD#2, and then power on both of them immediately.
Hard disks in EDA800
If you are using EDA800, please choose IBM's hard disks for your
recording purposes. EDA800 and IBM's hard disks have the best
compatibility.
No limitation for motion setup
There are only 50 sets of motion configuration settings for V1.20 or
earlier version. Now, there is no limitation for V1.21 (or later
version).
Administrator's Guide and Operating Instructions
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