Explosion-proof, Intrinsically Safe, Ground and Continuity Control

 

Model TR-7 Safe-T-Ground provides continuous monitoring of a truck ’s ground connection throughout loading operations.Static electricity is often brought in by tank trucks entering the loading area.The Safe-T-Ground Model TR-7 instantly stops loading operations if a tank truck loses its ground.The simple but rugged Model TR-7 circuit continuously measures resistance through the truck by applying a small voltage to one terminal of the truck grounding contactor.The other terminal is connected to the loading rack ground.If the Safe-T-Ground detects a resistance of more than a few ohms across the contactor terminals,the relay opens,breaking the control circuit.The relay will not close until the grounding contactor is properly connected. To safeguard loading operations,the Safe-T-Ground circuit can be wired into your pump control – and to an audible alarm or signal light..
The double wire TR-7 system provides an extra safeguard against explosion,compared to single wire grounding,which cannot measure the quality of the electrical ground connection during loading.The transistorized TR-7 circuit generates little heat – an added safety feature.. The Model TR-7 Safe-T-Ground is simple and easy to install.Removal of the cover on the explosion-proof aluminum housing reveals the easily accessible terminal strip for relay and ground control wiring,and a complete schematic wiring diagram appears on a label next to the terminal strip for easy wiring.Coiled grounding cable/contactor-handle assembly is easily replaced via mil-spec connector on housing.

Housing: 356-T6 Cast aluminum alloy (copper-free), explosion-proof – Class I, Group D.
Size: 6-5/8W x 10-3/8H x 5-5/8D.
Power Requirements: 105-125 VAC, 60 Hz. 7.75 watts – with light, 1.75 watts – without lights. Optional 220-240 VAC, 50/60 Hz - call factory.
Electrical Rating, Relay: DPDT, 10 amps, 125 VAC, 60 Hz. contact rat-ing.
Wiring Hookup: On terminal strip.
Conduit Connection: 3/4NPT
Installation: 7/16? mounting lugs, integrally cast.
Contactor: (Grounding clamp) molded polyethylene with beryllium copper contact clips. 16-2 type SO coiled cable; retracts to 3' extends to 16'.
Grounding Studs: 2 supplied. Order a pair for each truck.
Shipping Weight: 20 lb with contactor and cord.
Options: IIntegral pilot lights; 30' coiled cable; temporary contactor assemblies, clamp connecters and other supply voltages.