ABB LLC44B30A SSAC Liquid Level Control

ABB LLC44B30A is an SSAC LLC44 series liquid level control designed for monitoring and controlling conductive liquid levels in industrial and electrical control applications. The device combines a 120 VAC control supply, 50/60 Hz operating frequency, relay-based output switching and a fixed time-delay function within a compact plug-in housing. Its complete identification is important when selecting the correct liquid-level controller because the LLC44 family contains several configurations with different electrical and timing characteristics.

Available technical records identify the ABB LLC44B30A as a liquid level control with a 4 A rating, a 30 second fixed time-delay range, an isolated SPDT output and an 8-pin plug-in connection. These characteristics allow the controller to interface liquid-level sensing conditions with an external electrical control circuit. :contentReference[oaicite:1]{index=1}

Product Identification

• Manufacturer: ABB / SSAC
• Model: LLC44B30A
• Product Family: LLC44 Series
• Product Type: Liquid Level Control
• Supply Voltage: 120 VAC
• Operating Frequency: 50/60 Hz
• Switching Rating: 4 A
• Time Delay: 30 seconds fixed time-delay range
• Output: Isolated SPDT relay
• Connection: 8-pin plug-in
• Housing Type: Octal plug-in
• Approximate Dimensions: 45.2 mm × 60.7 mm × 73.9 mm

Liquid Level Control Function

The primary purpose of ABB LLC44B30A is to monitor liquid level conditions and provide a corresponding electrical relay output. In a typical conductive liquid-level control application, sensing electrodes are positioned at selected points within a tank or vessel. Changes in the liquid level alter the electrical condition detected by the controller.

The controller interprets the sensing condition and changes the relay output according to its configured operating function. This allows liquid level information to be incorporated into an electrical control circuit without requiring the sensing electrodes to directly operate the connected load.

This architecture can be useful in tanks, reservoirs, pumping systems and process equipment where liquid level must be monitored or used as a control input.

120 VAC Supply

The ABB LLC44B30A is specified for a 120 VAC control supply. The supply voltage is one of the most important identification characteristics because the LLC44 family contains versions designed for different electrical supply conditions.

The 120 VAC supply allows the controller to be integrated into control systems using the corresponding AC control voltage. The operating frequency is specified as 50/60 Hz, providing compatibility with electrical systems operating at either of these common power frequencies.

The actual installation should use a supply that corresponds to the rated electrical characteristics of the specific controller.

30 Second Fixed Time Delay

A key characteristic of the LLC44B30A is its 30 second fixed time-delay range. A time delay can be useful in liquid-level applications because liquid surfaces may move temporarily due to turbulence, pump operation, filling conditions or other process disturbances.

Without an appropriate delay, a rapidly changing liquid level could cause the relay output to switch repeatedly. The fixed delay provides a defined time period before the controller changes its output response according to the detected level condition.

The 30 second characteristic therefore forms an important part of the controller’s application behavior and should be considered when determining whether the device is suitable for a particular tank or pumping process.

Isolated SPDT Output

ABB LLC44B30A uses an isolated SPDT relay output. SPDT means single-pole double-throw and provides a common terminal together with normally open and normally closed contacts.

This arrangement gives the control system flexibility when interfacing the liquid-level signal with external equipment. Depending on the required control logic, the normally open or normally closed contact can be incorporated into a control circuit.

The isolated output also separates the sensing and control function from the external switched circuit, subject to the electrical ratings and installation requirements of the device.

4 Amp Switching Capability

Available product specifications identify the LLC44B30A with a 4 A switching rating. This rating is an important consideration when connecting the relay output to an external load.

The actual suitability of the relay depends on the load type, voltage, current and switching conditions. Resistive loads and inductive loads can place different demands on relay contacts.

For pump motors, solenoids or other inductive equipment, the control system should be designed with the applicable electrical protection and switching requirements in mind. The relay output should remain within the specified electrical limits of the controller.

8-Pin Plug-In Design

The LLC44B30A uses an 8-pin plug-in connection and belongs to the octal plug-in liquid level control category. This design allows the controller to interface with a compatible socket or mounting base while keeping the controller itself removable from the connection assembly.

A plug-in construction can simplify component identification and electrical servicing because the controller can be separated from the socket without removing every field wire from the installation.

The socket and terminal arrangement must correspond to the specific LLC44 configuration. Wiring should follow the appropriate electrical diagram rather than being determined solely from physical pin position.

Compact Housing

Current component specifications list approximate dimensions of 45.2 mm × 60.7 mm × 73.9 mm for the LLC44B30A. The compact housing allows the controller to be integrated into electrical control panels and liquid-level control assemblies where installation space is limited. :contentReference[oaicite:2]{index=2}

The physical dimensions are also useful when evaluating compatibility with existing sockets, panel layouts and enclosure arrangements. Mechanical clearance should be checked together with wiring access and surrounding components.

Conductive Liquid-Level Sensing

Liquid-level controllers of this type are intended for applications where the electrical characteristics of the liquid can be used for level detection. Conductive sensing electrodes can be positioned at specific levels in a tank, allowing the controller to determine when the liquid reaches or falls below a defined point.

The sensing method provides a simple interface between the liquid condition and the electrical control system. The suitability of conductive sensing depends on the electrical properties of the liquid and the electrode arrangement.

Different liquids can have significantly different conductivity, so the application should be evaluated before selecting a sensing configuration.

Level Control Applications

ABB LLC44B30A can be incorporated into liquid-level control systems where a relay output is required. A common application concept is controlling a pump according to the level of liquid in a tank.

In a pump-down arrangement, the controller can be used to respond when the liquid reaches a specified high or low sensing point. The relay output can then be connected to an appropriate control circuit that operates the pump or associated equipment.

Other applications can include level indication, alarm circuits, interlocking functions and process equipment monitoring.

Time Delay in Pump Control

Liquid-level control systems can experience rapid changes caused by turbulence, splashing or changes in pump flow. A fixed delay can help prevent immediate relay response to short-duration level changes.

The 30 second delay associated with the LLC44B30A is therefore relevant to applications where the control response should not occur immediately after a transient sensing condition.

The appropriate delay depends on the tank volume, pump capacity, process dynamics and required control sequence. These factors should be evaluated before integrating the controller into an automatic pumping system.

Relay Output Interface

The relay output provides a convenient interface between the level-sensing controller and an external electrical circuit. Rather than connecting the sensing electrodes directly to the controlled load, the controller processes the sensing condition and provides a relay contact for the control circuit.

This arrangement allows the liquid-level signal to participate in conventional electrical control logic. The SPDT configuration also provides both normally open and normally closed switching options.

The external circuit must remain within the specified voltage and current limits of the relay contact.

Technical Specification Table

Industrial Automation Integration

Liquid-level control is an important function in many industrial automation systems. Tanks, reservoirs and process vessels frequently require automatic monitoring to prevent overflow, avoid low-level conditions or coordinate pump operation.

The LLC44B30A provides a relay-based interface that can be incorporated into these systems. The relay output can become part of a larger control circuit involving contactors, motor starters, alarms or other automation components.

The controller itself should be considered as a level-sensing and relay-interface device rather than as a complete motor-control system.

Pump Control Considerations

When the LLC44B30A is used as part of a pump-control arrangement, the pump’s electrical power should normally be handled by equipment appropriate for the motor’s voltage and current. The liquid-level controller provides the control signal rather than necessarily switching the motor power directly.

A contactor, motor starter or suitable control interface can be used where required by the pump’s electrical characteristics. The LLC44B30A relay contact should be applied within its specified rating.

This arrangement provides a scalable way to integrate level sensing into industrial pump-control systems.

Electrical Isolation

The isolated SPDT output is an important characteristic of the LLC44B30A. Electrical isolation can help separate the controller’s sensing and control circuitry from the external circuit being switched.

Isolation is particularly useful when a level-sensing device must interact with another control voltage or circuit. The exact isolation characteristics should be confirmed from the applicable technical documentation when isolation voltage is an engineering requirement.

Installation Considerations

Installation of the LLC44B30A should consider the supply voltage, socket configuration, sensing electrodes, relay output wiring and environmental conditions. The 120 VAC supply must be correctly connected to the controller.

The sensing electrodes should be positioned according to the required liquid-level control points. Electrode placement determines the level conditions at which the controller responds.

The installation should also provide appropriate separation between control wiring and other electrical circuits where required by the system design.

Maintenance and Troubleshooting

Troubleshooting an LLC44B30A liquid-level control can begin with verification of the supply voltage and frequency. The 120 VAC supply should be checked before investigating the sensing circuit or output relay.

The sensing electrodes and associated wiring should then be inspected for continuity, contamination, incorrect connections or unsuitable electrode placement. The liquid’s conductivity can also affect sensing performance.

If the input sensing condition is correct but the relay output does not respond as expected, the relay circuit and socket connections should be examined. The fixed 30 second delay should also be considered during functional checks.

Model Identification

The complete model number ABB LLC44B30A should be retained in technical records. The LLC44 series contains numerous variations, including different supply voltages, time characteristics and output configurations.

For this reason, using only “LLC44” as the component identification is insufficient for accurate replacement or engineering documentation. The complete suffix “B30A” is necessary to distinguish this configuration from other LLC44 models.

This is particularly important when maintaining older industrial control systems where the exact electrical characteristics of the installed level controller must be preserved.

Relationship to the SSAC Product Family

LLC44B30A is associated with the SSAC liquid-level control product family. Current component databases also identify the same part under Littelfuse, while industrial component records continue to associate the model with ABB SSAC. :contentReference[oaicite:3]{index=3}

This product-history relationship is useful when searching technical documentation or component databases for legacy equipment. Engineers may encounter ABB, SSAC, SymCom or Littelfuse references when researching related liquid-level control products.

The complete model number remains the most useful identification reference when comparing technical records.

Compatibility Evaluation

Before replacing an LLC44B30A, the supply voltage, frequency, output contact arrangement, switching rating, time-delay characteristic and pin configuration should be compared with the existing control system.

A visually similar liquid-level controller may not provide the same electrical response. For example, a controller with a different supply voltage or time delay can produce different system behavior even if its housing and connector appear similar.

The complete ABB LLC44B30A designation should therefore be used as the starting point for compatibility evaluation.

Control Logic

The SPDT relay output provides flexibility for control logic because both normally open and normally closed states are available. This allows the same basic relay configuration to participate in different control arrangements.

The selected contact can be incorporated into a pump-control circuit, alarm circuit or interlocking circuit depending on the application. The actual logic depends on how the relay contacts are wired within the overall system.

The controller’s time-delay behavior should be incorporated into the control sequence when designing or troubleshooting the application.

Technical Documentation

For an equipment database or industrial component catalog, the recommended identification is “ABB LLC44B30A — SSAC Liquid Level Control, 120 VAC, 4 A, 50/60 Hz, 30 Second Fixed Time Delay, Isolated SPDT Output, 8 Pin.”

This format preserves the most important technical identifiers while clearly distinguishing the model from other members of the LLC44 family.

Documentation should also include the associated socket, electrode arrangement and external control circuit where these details are available.

Conclusion

ABB LLC44B30A is an SSAC LLC44 series liquid level control designed for conductive liquid-level monitoring and relay-based control applications. Available technical records identify the unit with a 120 VAC supply, 50/60 Hz operating frequency, 4 A switching rating, a 30 second fixed time-delay range, isolated SPDT output and 8-pin plug-in connection. :contentReference[oaicite:4]{index=4}

The controller provides a practical interface between liquid-level sensing electrodes and an external electrical control circuit. Its isolated SPDT relay output allows normally open and normally closed control arrangements, while the fixed time-delay characteristic can help provide a defined response to changing liquid-level conditions.

The compact octal plug-in construction and documented 45.2 mm × 60.7 mm × 73.9 mm approximate dimensions make the device suitable for integration into control panels and liquid-level control assemblies. :contentReference[oaicite:5]{index=5}

For technical identification, ABB LLC44B30A should always be recorded using its complete model designation. The 120 VAC supply, 4 A switching rating, 30 second time-delay characteristic, isolated SPDT output and 8-pin connection are key parameters when evaluating the controller for liquid-level monitoring, pump-control and industrial automation applications.