MTH Crossing gates for a HO layout - problem

[BillNCR]

I installed  MTH Railroad crossing gates on my layout, details:-

 Power supply – 16V / AC

Single line HO track – always one direction

Location of approach sensor -  5 Ft. prior to crossing

Location of departure  sensor -  8 inches after crossing

 

When train approaches crossing , bells sound and gates lower, , prior to train arrival.  (9 seconds, just as manual says)

 After train passes gates, and over the departure sensor, the bells continue to ring and boom stays down for 60 + seconds..

 There is no mention in the manual of being able to vary the time the gates stay down.  The manual does say the system is bi – directional, however, if I coverer the “departure” sensor, it does not activate the bells / booms   …

 

Sent email to MTH, no reply (yet)  ..Any assitance will be appreciated  ..

Regards, Bill