Gasboy Atlas Fuel Systems Installation Manual - Manual (Page 65)

MDE-4331M Atlas® Fuel Systems Installation Manual · September 2014 Page 7-3
Electrical Requirements Reference Information
STP Control Relay Boxes for Dispensers
Following are the STP control relay box requirements for the unit:
• Gasboy requires the installation of STP isolation relays in addition to STP control relays.
Combined STP control relay/isolation relay boxes are recommended.
• Each STP requires a separate control relay.
• Dispenser relay must not be used to power the STP.
STP Isolation Relays for Electronic Dispensers
STP isolation relays provide electrical isolation between dispensers and prevent damage from
cross phasing. For more information, refer to MDE-4334 Commercial and Retail Series Atlas
Start-up/Service Manual and FE-357 Field Wiring Diagram Atlas Retail/Commercial Pumps
Electronic and Mechanical Units.
Note: For a three-phase STP, use isolation relay at the input of the three-phase STP control
box.
• Gasboy requires the installation of STP isolation relays in addition to STP control relays.
Combined STP control relay/isolation relay boxes are recommended.
• Isolation relays must be installed for each STP control line at every dispenser or dispenser
grouping on a single circuit breaker.
• A neutral wire must be routed to control relays from the dispenser circuit breaker. For
more information, refer to FE-356 Field Wiring Diagram Atlas Retail, Commercial, E85,
and DEF Dispensers with Electronic and Mechanical Displays.
Conduit
It is recommended that a spare conduit must be run for future high-speed communications.
• Use a minimum 1-inch conduit for all Gasboy pumps/dispensers.
• Run all power and light wires in a threaded, rigid metal conduit, or a rigid non-metallic
conduit. The conduit must conform to national and local electrical codes. If a non-metallic
conduit is used, it must be at least 2 feet underground. The last 2 feet of the underground
run to the J-box must be a rigid metal conduit or threaded steel intermediate metal conduit.
• Never share the conduit or wire troughs with any other manufacturer’s equipment (that is,
speaker wires, and so on).
Note: The same conduit may be used for routing power to the pump/dispenser and retail
two-wire data loop. The two-wire data loop is a class 1 circuit.
• A metal conduit is not sufficient to provide an equipment ground. A separate ground wire
must be used.
• Knock-out boxes or flexible conduits are not permitted for installation.
Note: Extra J-boxes that are added to the pump/dispenser must be listed class 1,

division 1, group C and D explosion-proof.
• All electrical fittings must be listed for class 1, group C and D hazardous locations as
required by NFPA 30A and NFPA 70.
• A seal-off ‘Y’ fitting (for example, Killark ® Type EY) must be installed on all units as the
first connection where the conduit leaves the ground.