5754ODPE woes

Hi all,

I'm experiencing problems with the 57540ODPE's

I have a commercial install where the corridor lighting is C-Bus controlled, due to variations in the corridor construction, four different sensors are used; 5753L(10), 5751LWE(6), E5750WPL (30) and 5754ODPE(20).

There are two operating modes; occupied and security, when the security mode is on the PIR's are active operating minimum lighting, when the occupied mode is on, all lighting is on and the PIR's are disable.

Only the two GA's are used, with only the 'occupied' GA being switched via a touch screen, this GA is also used to disable the PIR's and 'OR' logic is employed in the output relays to achieve the mode switching .

As always I set the PIR's to a short duration (10secs) to walk test the system, on success the PIR's are then re-timed to the desired timeout.

The problems are:
1: After resetting the timeout, a small number of the 5754's no longer detect movement, the blue light is on, but nothing else. I've checked the programming, I've re-set to default and re-programmed but with no success, supply voltage is OK, and other adjacent 5754's operated correctly.
2, Two seem to be locked in disabled mode (no light on) at all, fail to detect movement but can be programmed?

I've a faulty one rigged it up not the bench and programmed it to simply switch on when it detects movement, but again it failed to work. I now have 6 of this type displaying this fault condition, any ideas? has anyone seen this before? or am I missing something.?

Paul.