Overview, Materials required, Testing the s404 – Franklin Fueling Systems S404 Liquid Sensor User Manual
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Overview
The S404 Liquid sensor is a component of the DC404
Dispensing Cutoff System, and is used to detect the
presence of a liquid in the normally dry Class 1, Division 1,
Group D Hazardous Areas. The sensor is supplied with a
QuickOn connector and 25 feet of cable. The S404 liquid
sensor uses magnetic-float /reed-switch technology (the
sensor must be suspended vertically so the float can rise
freely with the level of a liquid).
When the float rises more than 1/2 of an inch, the
magnetically sensitive reed switch will open. The open
circuit is then recognized by the 404-4 controller which
shuts down power to the STP or dispenser.
Materials Required
Wire cutters to trim the senor wires in the Quickon
Connector.
ELECTRICAL DANGER Avoid electrical shock
hazards: ensure all power going to the ATG
console is turned off, tagged, and locked-out at
the power panel before doing any maintenance
or installation work at the ATG console.
Installation Sequence
1. Shut off power to the dispenser or STP.
2. Install the 404-4 controller in accordance with it’s
installation instructions.
404-4 Controller
Cable
Connection
STP Electrical
Junction Box
S404 Sensor
STP Sump
EYS
Figure 1: Installation in STP Sumps
3. Using the supplied QuickOn connector connect the
404-4 to the S404 Liquid Sensor.
a. Insert the S404 cable through one end of the
connector.
b. Pull the white wire from the S404 into the
white slot on the connector.
c. Pull the black wire from the S404 into the
black slot on the connector.
d. Trim the wire back to the body of the
connector.
e. Repeat this process with the cable from the
404-4.
Assemble the connector.
4. Test the sensor (verify that the system shuts down
power) Refer to Testing the S404 on the next page.
5. Lower the sensor to the bottom of the STP sump,
dispenser pan or tank interstitial, ensuring that the
sensor remains vertical so that the float can rise
freely with the level of any liquid.
404-4
Controller
S404 sensor
Dispenser
Junction Box
EYS
Dispenser
Sump
Cable Connection
Dispenser
Base
EYS
Figure 2: Installation in Sumps / Dispenser Pans
Testing the S404
Testing this device is a matter of inverting the sensor 180
degrees with the bottom up, to trigger the shutdown of the
STP or dispenser. Test the sensor for proper operation
immediately after installation, and at least once annually.