Liquip overfill monitors offer the option of grounding integrated in the same housing, which reduces investment, installation and maintenance costs, in addition to optimizing the space available on the platform.

Mounted in explosion-proof and corrosion-resistant panels, the overfill and / or grounding monitors are fail-safe (Self-Checking), have status LEDs that provide high visibility and greater durability compared to conventional bulb lamps.

The equipment is available in the supply voltages of 110Vac and 220Vac in the frequency of 60Hz and has approval and NBR / ATEX certification for use in classified areas of Zone 1 and Group IIB, which comprises the most diverse and common liquids and combustible gases and / or flammable. For more information about the list of products from groups IIB and IIA allowed, contact Redlands do Brasil Ltda.

Serie RM100


The Liquip Overfill Monitor of the RM100 series incorporates the most modern technology for overfill monitoring. Simultaneously monitors 2 (two) and 5 (five) wire optical technology sensors and thermistor and can monitor up to 12 5 (five) wire optical technology overfill sensors and up to 8 2-wire optical technology or thermistor sensors.


Like the other overfill equipment manufactured by Liquip, it incorporates in the same equipment, the grounding system with “Diode Check” technology for greater system security.


Available in a single version, it can be easily configured in the field using switch switches, including the supply voltage, 120Vac or 220Vac, optical technology or thermistor, 2 (two) or 5 (five) wire sensors, resistive grounding via alligator clip or API plug and “Diode Check” system.


The equipment is mounted in an explosion-proof and corrosion-resistant enclosure, with up to 03 (three) ¾ ”NPT connections, 02 (two) on the left side, for the supply and output of permissive system signals (TAS) and 1 (one) at the bottom to connect the intrinsically safe (IS) signals.


With a larger display and excellent visibility, it has a system of independent LEDs for easy visualization and identification of the failure status. There are 3 (three) LEDs, one blue for identifying the ground, red for “NOT PERMISSIVE” and green for “PERMISSIVE” of the system. Side LEDs inform the system’s mode of operation (2 or 5 wire sensors) and the number of sensors being monitored. These LEDs also identify the wet or defective sensor for easy repair and reduction of unproductive time for the terminal and the tanker.


By-Pass is performed using a remote digital key that must be positioned on the front of the equipment. The By-Pass is enabled only after the grounding check for greater safety and returns to normal status after disconnecting the API plug or interrupting the grounding signal.



Model PD501


The Liquip Overfill Monitor of the PD501 series can be configured in a variety of ways, such as a 5 (five) wire optical system for monitoring up to 15 sensors or as a single channel monitor, for a 2 ( two) wires or 2 (two) wires thermistor for monitoring a single sensor or compartment, as for example in the case of loading on non-compartmentalized trucks or tank cars.


The PD501 overfill monitor has a “Diode Check” grounding system for added safety.


The equipment is mounted in an explosion-proof and corrosion-resistant enclosure, with up to 04 (four) ¾ ”NPT connections, 02 (two) at the top to connect the system’s power and permissive cables and 02 (two) at the bottom part for connection of the intrinsically safe signal cables (IS) and 2 (two) high visibility status LEDs, GREEN for “PERMISSIVE” and RED for “NOT PERMISSIVE” of the system.


It is available in the supply voltages of 110Vac and 220Vac in the frequency of 60Hz, has output signal via relay contact of 5A / 240V for permissive of the system (Terminal Automation System) and maximum response time of up to 0.5 second after the detection of overfill, ground fault or interruption, if enabled.


General features:
-Overfill monitor with Optical technology or Thermistor of 5 (five) or 2 (two)
-Integrated ground monitoring with resistive technology and “Diode Check” mode for greater safety
-Allows loading only if connected to the Tank Truck
-Mounted in explosion-proof enclosure for classified area Zone 1 and Group IIB
-Green and red LEDs for easy identification and visualization of system status
-5A / 250VAC output relay for system permissive
-By-pass switch mounted on the front panel of the “PadLock” type equipment for use by authorized personnel only.




Overfill API plug is made of polyurethane (engineering plastic) with up to 10 stainless steel pins for connecting 2 and 5 wire sensors (optical technology or thermistor).


The cable is spiral up to 8 meters long and 10 wires with polyurethane protective coating for greater resistance to petroleum derivatives.


Spiral cable and API plug meet API standard RP1004.


The set (Cable & Plug) is responsible for the connection with the Tank Truck socket for monitoring the overfill and / or grounding system during the loading or transfer operation at the terminal.


It can be supplied in 2 (two) versions:

GP103 – For optical technology overfill system
GP104 – For thermistor technology overfill system

To ensure the grounding of the Tanker Truck. Before connecting any other equipment to the truck, first connect the alligator clip or API plug in an appropriate location for the dissipation of static electricity and safety of operation.


The alligator clip is made of cast aluminum with stainless steel tapered point screws.


The cable can be spiral or smooth, up to 8 meters in total length.


It can be supplied in 2 (two) versions:

-EAC201 – Flat Cable and Ground Alligator Claw
-EAC202 – Spiral Cable and Alligator Grounding Claw

The socket is mounted on the tanker and is responsible for connection to the API plug of the terminal monitoring system. Can monitor grounding and overfill simultaneously.


It is manufactured according to API standard RP1004 in aluminum, with plastic cover for dust protection, and stainless steel pins that guarantee better contact and greater durability.


It can be supplied with or without the ground bolt screw.


It is fully compatible with all overfill and grounding systems and technologies on the market.

Made of aluminum with wire interconnection terminals With ¾ ”NPT connections for intrinsically safe signal wires input and output and connection of the grounding alligator plug and clamp cables.

Allows for quicker and safer intervention, replacement or reconnection of cables, without the need to interrupt the platform or platforms in case the system needs repair


It can be supplied in 2 (two) versions:

JB100 – With 2 (two) ¾ ”NPT connections
JB103 – With 3 (three) ¾ ”NPT connections (in case of installing a secondary ground cable or separately)

Liquip overfill sensors can be optical or thermistor and are made of aluminum for use in petroleum products or glass for use in applications that require greater compatibility and chemical resistance.


They are manufactured in accordance with the API RP1004 standard and are intrinsically safe (IS) certified for use in hazardous areas and can be installed on tank trucks, on Top Loading loading arms or even in portable applications, such as, for example, loading tank wagons.