EXT- = bell trig
12v = Hold Off +
GND = Hold Off -
Z29 = Tamper return but may need a relay
IN- = Strobe -
For some reaon I cant load up your bellbox images
if fail safe locks then more use will extend but by seconds imo. You can calculate it using batts but bear in mind all A/h stats are based on a 24 hr discharge
It's not just you someone else will soon be around undercutting you, then realise they can't make it pay and go back to working for a firm they were undercutting before.