Tim Lamb formulated on Sunday :
That is what we have. Key release on the external crank access. Very low
geared so it only opens slowly.

Mine is painfully slow to hand crank too, but fine when powered. I only
found out how slow when I tried it out of curiosity, luckily I have
never had a failure. I suppose if I lost power often, I would either
make a battery backup system (it is 24v DC), or make an attachment to
fit my battery drill to crank it.