Installation Recommendations for FDMs

The following recommendations should be followed when considering the installation location and mounting for FDMs.

The cable connecting an FDM to the Enabler PCI Card should:

be routed (as much as possible) away from sources of Electromagnetic Noise.
for protocols using Active FDMs this connection is RS232, so should be no longer than 10 meters

FDMs should be mounted in a case to protect them from tampering and accidental damage.
If Lightning protection is required, this should be installed between the FDM and Enabler Card.
Check you are using the correct Power supply for the FDM you are using. This is documented in detail in our Power Supply requirements FAQ.

Choosing a Location

FDM cards are normally mounted in the main switchboard area of the site with an RS232 connection back to The Enabler PCB in the site server PC. You will need to determine the best housing solution depending on:

The requirements for the site (e.g. number and type of FDM cards)
The requirements of local authorities
Availability of power supply for FDM cards

Case Selection

Where no existing housing can be (re)used, or where separate housing is desirable then a suitable polycarbonate housing with appropriate UL ratings should be used.

These can be obtained from any component supplier such as RS or Farnell in most countries. We are aware that some integrators have used specially designed cases incorporating space for the FDM power supply.

Cable Selection

Enabler PCI to FDM

When selecting cable to connect The Enabler PCI card to FDM cards you should consider the following:

RS232/RS485	Cabling should be high quality, low-loss shielded communications cable as sold for RS232 applications. Recommended type for RS232 or RS485 should be 2, 3 or 5 core, fully insulated, shielded and sheathed with tinned drain wire.
IFSF over LON	The cabling should be Level 4, 22 AWG Network cabling or equivalent (stranded or un stranded pair with PVC outer - no shielding is required).

FDM to Pumps

When selecting cable to connect the FDM card to the Pumps you should consider the following.

The Forecourt Distribution module has two functions depending on the type (Active or Passive).

Active FDMs provide physical signal conversion as well as a termination and isolation point for dispenser cabling.
The Passive FDM only provide termination and isolation points for dispenser cabling.

In either case, communications cables from EACH dispenser should be run back to the FDM. This allows each dispenser to be isolated individually in case of problems with any one dispenser.

It is important to note that in some countries, special requirements will be laid down by regulatory authorities (e.g. steel wire armoured cable). Also some specific manufacturer requirements exist in some markets.

The recommendations of the dispenser manufacturer should be sought and followed in all cases as well as the requirements of local regulatory authorities.

Where they are available, notes on cable selection are now included in the Pump Connection FAQ pages.