TRM-DFS

TRM-DFS-3 is designed to detect leaking diesel fuel in dry, indoor locations. The sensor is positioned on a concrete floor or in shallow drip pan below day tanks, beneath flex coupling hoses and fuel filters, on pump pads and below valve manifolds. Reaction time to diesel fuel is less than 10  seconds after contact.

The sensor body has a low center of gravity to sit stably on a flat surface. (An optional stainless hold-down fixture is available.) A replaceable sensor element extends from the bottom surface of the DFS-3 and the element design incorporates a natural springiness to assure that the element is held in contact with the floor surface. Minimum puddle depth required for detection is virtually zero.

TRM-DFS-3 emulates a closed dry contact (resistance when new is less than 100 ohms). When a puddle of leaking diesel fuel reaches the sensor, the resistance climbs to over 1 meg-ohm in seconds. For many Building Management (BMS), PLC, or Alarm systems, a single TRM-DFS-3 can be connected directly to a Dry Contact input as a normally closed device that “opens-on-alarm”. However, in most installations more than one TRM-DFS-3 will be deployed. In order to reduce the count of BMS inputs, a TRM-Easy5-Relay or TRM-Easy5-Panel can be used to monitor up to 20 of the TRM-DFS-3 sensors and consolidate their alarm status to a one or two output relay signals.

TRM-DFS-3 is resettable and the sensor element can be removed and replace in a matter of seconds. Many users choose to keep spare sensor element on hand to quickly restore system operation after a leak incident and clean-up. The “wet” element can be allowed to evaporate and dry to its reset state and returned to the spares pool for future use.

TRM-DFS-3 will also detect and respond to gasoline, jet fuel, heavy fuel oils and other liquid hydrocarbon fuels.

TRM-DFS-3 has been independently tested to EPA 3rd party test protocols by an independent 3rd party testing facility.   TRM-DFS-3 is listed on the national data base of approved sensors published by the National Working Group on Leak Detection Evaluations (NWGLDE)

See  a list of Frequently Asked Questions Here.

Take a look at typical systems designs and Bills of Material.

Form Factor:

• Compact, low center of gravity for stable positioning on flat surface – Stainless steel hold down fixture available.

Dimensions:

• 3” diameter, 1” thick

Leader cable:

• Supplied with factory standard 2m (6 feet) of two wire leader cable. Wago Lever-Nut quick connects are supplied to daisy chain multiple DFS-3 devices or to connect to jumper cables. (Maximum recommended jumper cable per daisy chain is 330feet)

Sensor Element:

• Replaceable in field without tools.

Integrity Monitoring:

• Missing or damaged sensor element or damaged/disconnected jumper wire generates an alarm condition. This is a “fail safe” design approach because the sensor cannot signal normal conditions while unable to detect a leak.

Response time:

• Diesel, Gasoline, Jet Fuel, E85 blend: < 10 seconds
• Heavy Fuel Oil: up to 3 minutes depending on viscosity and temperature (consult factory)

Reset time:

• Varies by fuel type, ambient temperature and air flow. TRM Sensors recommends that users keep several spare sensor elements in maintenance stores. Swap in a clean and dry sensor element to quickly restore system and let the “wet” element evaporate to its reset condition over several days.

Simple Apparatus Statement:

• CSA Group has examined TRM-DFS-3 and considers the sensor to be “Simple Apparatus” per CSA /EN/IEC/UL 60079-11 Clauses 5.7 a and b. As such TRM-DFS-3 may be installed in hazardous areas when connected to the monitoring device via an approved zener safety barrier. The safety approvals granted to the zener barrier apply to the installation as a whole. TRM Sensors recommends the MTL 7760ac zener barrier. Up to 10 TRM-DFS-3 barriers may be connected to a single TRM Relay Unit Type-CV via a single barrier.
• 3rd Party US EPA test report by KWA Associates.

Performance Certification;

TRM-DFS-3 has been tested to US EPA test protocols by an independent 3rd party test facility

TRM-DFS-3 is listed on the national database of approved sensors published by the National Working Group on Leak Detection Evaluations.

Recommended monitoring options:

• Up to 20 TRM-DFS-3 may be monitored by TRM-Easy5-Panel (UL508A certified) or TRM-Easy5-Relay (UL approved DIN rail module) . In many cases a single TRM-DFS-3 may be connected directly to dry-contact inputs of a BMS, PLC or Alarm System panels. TRM-DFS-3 will emulate a normally closed contact (<100 ohms) that opens (> 1 meg-ohm) on alarm.