Level Control - Apollo Valves
Level control is essential for many industrial and commercial applications, ranging from simple water tanks to complex chemical processing systems. Industrial applications often require control to maintain safe and efficient operations. This can be accomplished through the use of float switches or differential pressure control. Float switches are devices used to measure the level of a liquid in a tank. They work by using a float that is attached to a switch. When the float rises or falls with the level of the liquid, the switch is activated. This can then be used to trigger an alarm or shut off a pump. Differential pressure control is another level control method that uses pressure sensors to measure the difference in pressure between two points. This can be used to determine the liquid level in a tank. Differential pressure control is often used in applications requiring precise level control. At Centro, we carry a complete selection of level-control products to meet your needs. Our float switches are ideal for small-scale applications, while our radar and differential pressure control systems are designed for more demanding environments. We also offer load cells for use in weight-based level measurement. Whether you need a simple float switch or a sophisticated differential pressure system, Centro has your level control products.
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Part number 2080500 from Apollo is a Water Gauge 1/2". Typical applications span industrial processing, plumbing, and HVAC environments. Backed by Apollo's commitment to quality, the 2080500 is built to perform under real-world conditions.
$248.04$293.68
Available for Purchase
Subject to factory lead times
Part number 2080501 from Apollo is a Bronze Water Gauge 1/2". This product serves professionals across commercial mechanical systems, industrial processing, and fire protection sectors. The 2080501 reflects Apollo's long-standing reputation for quality and innovation. It is designed to comply with applicable NSF and ASME requirements.
$124.50$147.41
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2080502 is a Bronze Water Gauge 1/2". This product serves professionals across industrial processing, plumbing, and HVAC sectors. Apollo products are trusted by engineers and specifiers worldwide. It is designed to comply with applicable NSF and UL requirements.
$102.22$121.03
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2080503 is a Bronze Water Gauge 1/2". Typical applications span oil and gas, HVAC, and plumbing environments. As a leader in valves and flow control, Apollo manufactures every component to exacting standards. This product meets relevant UL and FM standards.
$240.33$284.55
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2110400 is a Bronze Water Gauge 1/2". It is commonly found in plumbing, oil and gas, and marine applications. Backed by Apollo's commitment to quality, the 2110400 is built to perform under real-world conditions. This product meets relevant ASME and FM standards.
$204.92$242.62
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2110401 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, oil and gas, and industrial processing sectors. As a leader in valves and flow control, Apollo manufactures every component to exacting standards. It is designed to comply with applicable UL and FM requirements.
$83.55$98.92
Available for Purchase
Subject to factory lead times
The Apollo 2110402 is a Bronze Water Gauge 1/2". It is commonly found in fire protection, marine, and oil and gas applications. Backed by Apollo's commitment to quality, the 2110402 is built to perform under real-world conditions.
$99.12$117.36
Available for Purchase
Subject to factory lead times
The Apollo 2110403 is a Bronze Water Gauge 1/2". Typical applications span fire protection, industrial processing, and commercial mechanical systems environments. Apollo Valves is recognized globally for engineering products that meet strict performance standards. This product meets relevant ASME and UL standards.
$197.06$233.32
Available for Purchase
Subject to factory lead times
Part number 2110500 from Apollo is a Water Gauge 1/2". Typical applications span fire protection, industrial processing, and commercial mechanical systems environments. The 2110500 reflects Apollo's long-standing reputation for quality and innovation.
$204.92$242.62
Available for Purchase
Subject to factory lead times
The Apollo Valves 2110501 is a Bronze Water Gauge 1/2". Typical applications span plumbing, oil and gas, and fire protection environments. Apollo Valves is recognized globally for engineering products that meet strict performance standards.
$83.05$98.33
Available for Purchase
Subject to factory lead times
The Apollo Valves 2110502 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, fire protection, and oil and gas sectors. As a leader in valves and flow control, Apollo manufactures every component to exacting standards. This product meets relevant UL and NSF standards.
$96.70$114.49
Available for Purchase
Subject to factory lead times
The Apollo Valves 2110503 is a Bronze Water Gauge 1/2". It is commonly found in plumbing, commercial mechanical systems, and marine applications. Backed by Apollo's commitment to quality, the 2110503 is built to perform under real-world conditions.
$197.06$233.32
Available for Purchase
Subject to factory lead times
The 2115000 from Apollo is a Bronze Water Gauge 1/2". This product serves professionals across commercial mechanical systems, plumbing, and marine sectors. Apollo products are trusted by engineers and specifiers worldwide.
$217.76$257.83
Available for Purchase
Subject to factory lead times
The 2115001 from Apollo is a Bronze Water Gauge 1/2". Typical applications span fire protection, oil and gas, and plumbing environments. The 2115001 reflects Apollo's long-standing reputation for quality and innovation. This product meets relevant ASME and UL standards.
$91.29$108.09
Available for Purchase
Subject to factory lead times
The 2115002 from Apollo is a Bronze Water Gauge 1/2". It is commonly found in oil and gas, industrial processing, and marine applications. Apollo Valves is recognized globally for engineering products that meet strict performance standards.
$106.95$126.63
Available for Purchase
Subject to factory lead times
The 2115003 from Apollo is a Bronze Water Gauge 1/2". This product serves professionals across commercial mechanical systems, fire protection, and industrial processing sectors. The 2115003 reflects Apollo's long-standing reputation for quality and innovation. It is designed to comply with applicable FM and ASME requirements.
$209.79$248.39
Available for Purchase
Subject to factory lead times
The Apollo Valves 2115100 is a Bronze Water Gauge 1/2". It is commonly found in plumbing, commercial mechanical systems, and marine applications. Apollo Valves is recognized globally for engineering products that meet strict performance standards.
$217.76$257.83
Available for Purchase
Subject to factory lead times
The Apollo Valves 2115101 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, fire protection, and oil and gas sectors. Apollo products are trusted by engineers and specifiers worldwide. It is designed to comply with applicable UL and NSF requirements.
$90.67$107.35
Available for Purchase
Subject to factory lead times
Part number 2115102 from Apollo is a Bronze Water Gauge 1/2". It is commonly found in fire protection, marine, and plumbing applications. Apollo products are trusted by engineers and specifiers worldwide. It is designed to comply with applicable NSF and FM requirements.
$104.42$123.63
Available for Purchase
Subject to factory lead times
Part number 2115103 from Apollo is a Bronze Water Gauge 1/2". Typical applications span fire protection, industrial processing, and commercial mechanical systems environments. Backed by Apollo's commitment to quality, the 2115103 is built to perform under real-world conditions.
$209.79$248.39
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2120400 is a Bronze Water Gauge 1/2". It is commonly found in industrial processing, plumbing, and HVAC applications. Apollo products are trusted by engineers and specifiers worldwide. This product meets relevant NSF and UL standards.
$234.77$277.97
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2120401 is a Bronze Water Gauge 1/2". Typical applications span commercial mechanical systems, industrial processing, and oil and gas environments. Apollo Valves is recognized globally for engineering products that meet strict performance standards. It is designed to comply with applicable NSF and FM requirements.
$95.68$113.28
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2120402 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, oil and gas, and industrial processing sectors. The 2120402 reflects Apollo's long-standing reputation for quality and innovation. This product meets relevant UL and NSF standards.
$109.35$129.47
Available for Purchase
Subject to factory lead times
The Apollo 2120500 is a Bronze Water Gauge 1/2". This product serves professionals across oil and gas, fire protection, and industrial processing sectors. The 2120500 reflects Apollo's long-standing reputation for quality and innovation.
$234.77$277.97
Available for Purchase
Subject to factory lead times
Part number 2080500 from Apollo is a Water Gauge 1/2". Typical applications span industrial processing, plumbing, and HVAC environments. Backed by Apollo's commitment to quality, the 2080500 is built to perform under real-world conditions.
$248.04$293.68
Available for Purchase
Subject to factory lead times
Part number 2080501 from Apollo is a Bronze Water Gauge 1/2". This product serves professionals across commercial mechanical systems, industrial processing, and fire protection sectors. The 2080501 reflects Apollo's long-standing reputation for quality and innovation. It is designed to comply with applicable NSF and ASME requirements.
$124.50$147.41
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2080502 is a Bronze Water Gauge 1/2". This product serves professionals across industrial processing, plumbing, and HVAC sectors. Apollo products are trusted by engineers and specifiers worldwide. It is designed to comply with applicable NSF and UL requirements.
$102.22$121.03
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2080503 is a Bronze Water Gauge 1/2". Typical applications span oil and gas, HVAC, and plumbing environments. As a leader in valves and flow control, Apollo manufactures every component to exacting standards. This product meets relevant UL and FM standards.
$240.33$284.55
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2110400 is a Bronze Water Gauge 1/2". It is commonly found in plumbing, oil and gas, and marine applications. Backed by Apollo's commitment to quality, the 2110400 is built to perform under real-world conditions. This product meets relevant ASME and FM standards.
$204.92$242.62
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2110401 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, oil and gas, and industrial processing sectors. As a leader in valves and flow control, Apollo manufactures every component to exacting standards. It is designed to comply with applicable UL and FM requirements.
$83.55$98.92
Available for Purchase
Subject to factory lead times
The Apollo 2110402 is a Bronze Water Gauge 1/2". It is commonly found in fire protection, marine, and oil and gas applications. Backed by Apollo's commitment to quality, the 2110402 is built to perform under real-world conditions.
$99.12$117.36
Available for Purchase
Subject to factory lead times
The Apollo 2110403 is a Bronze Water Gauge 1/2". Typical applications span fire protection, industrial processing, and commercial mechanical systems environments. Apollo Valves is recognized globally for engineering products that meet strict performance standards. This product meets relevant ASME and UL standards.
$197.06$233.32
Available for Purchase
Subject to factory lead times
Part number 2110500 from Apollo is a Water Gauge 1/2". Typical applications span fire protection, industrial processing, and commercial mechanical systems environments. The 2110500 reflects Apollo's long-standing reputation for quality and innovation.
$204.92$242.62
Available for Purchase
Subject to factory lead times
The Apollo Valves 2110501 is a Bronze Water Gauge 1/2". Typical applications span plumbing, oil and gas, and fire protection environments. Apollo Valves is recognized globally for engineering products that meet strict performance standards.
$83.05$98.33
Available for Purchase
Subject to factory lead times
The Apollo Valves 2110502 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, fire protection, and oil and gas sectors. As a leader in valves and flow control, Apollo manufactures every component to exacting standards. This product meets relevant UL and NSF standards.
$96.70$114.49
Available for Purchase
Subject to factory lead times
The Apollo Valves 2110503 is a Bronze Water Gauge 1/2". It is commonly found in plumbing, commercial mechanical systems, and marine applications. Backed by Apollo's commitment to quality, the 2110503 is built to perform under real-world conditions.
$197.06$233.32
Available for Purchase
Subject to factory lead times
The 2115000 from Apollo is a Bronze Water Gauge 1/2". This product serves professionals across commercial mechanical systems, plumbing, and marine sectors. Apollo products are trusted by engineers and specifiers worldwide.
$217.76$257.83
Available for Purchase
Subject to factory lead times
The 2115001 from Apollo is a Bronze Water Gauge 1/2". Typical applications span fire protection, oil and gas, and plumbing environments. The 2115001 reflects Apollo's long-standing reputation for quality and innovation. This product meets relevant ASME and UL standards.
$91.29$108.09
Available for Purchase
Subject to factory lead times
The 2115002 from Apollo is a Bronze Water Gauge 1/2". It is commonly found in oil and gas, industrial processing, and marine applications. Apollo Valves is recognized globally for engineering products that meet strict performance standards.
$106.95$126.63
Available for Purchase
Subject to factory lead times
The 2115003 from Apollo is a Bronze Water Gauge 1/2". This product serves professionals across commercial mechanical systems, fire protection, and industrial processing sectors. The 2115003 reflects Apollo's long-standing reputation for quality and innovation. It is designed to comply with applicable FM and ASME requirements.
$209.79$248.39
Available for Purchase
Subject to factory lead times
The Apollo Valves 2115100 is a Bronze Water Gauge 1/2". It is commonly found in plumbing, commercial mechanical systems, and marine applications. Apollo Valves is recognized globally for engineering products that meet strict performance standards.
$217.76$257.83
Available for Purchase
Subject to factory lead times
The Apollo Valves 2115101 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, fire protection, and oil and gas sectors. Apollo products are trusted by engineers and specifiers worldwide. It is designed to comply with applicable UL and NSF requirements.
$90.67$107.35
Available for Purchase
Subject to factory lead times
Part number 2115102 from Apollo is a Bronze Water Gauge 1/2". It is commonly found in fire protection, marine, and plumbing applications. Apollo products are trusted by engineers and specifiers worldwide. It is designed to comply with applicable NSF and FM requirements.
$104.42$123.63
Available for Purchase
Subject to factory lead times
Part number 2115103 from Apollo is a Bronze Water Gauge 1/2". Typical applications span fire protection, industrial processing, and commercial mechanical systems environments. Backed by Apollo's commitment to quality, the 2115103 is built to perform under real-world conditions.
$209.79$248.39
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2120400 is a Bronze Water Gauge 1/2". It is commonly found in industrial processing, plumbing, and HVAC applications. Apollo products are trusted by engineers and specifiers worldwide. This product meets relevant NSF and UL standards.
$234.77$277.97
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2120401 is a Bronze Water Gauge 1/2". Typical applications span commercial mechanical systems, industrial processing, and oil and gas environments. Apollo Valves is recognized globally for engineering products that meet strict performance standards. It is designed to comply with applicable NSF and FM requirements.
$95.68$113.28
Available for Purchase
Subject to factory lead times
Engineered by Apollo, the 2120402 is a Bronze Water Gauge 1/2". This product serves professionals across HVAC, oil and gas, and industrial processing sectors. The 2120402 reflects Apollo's long-standing reputation for quality and innovation. This product meets relevant UL and NSF standards.
$109.35$129.47
Available for Purchase
Subject to factory lead times
The Apollo 2120500 is a Bronze Water Gauge 1/2". This product serves professionals across oil and gas, fire protection, and industrial processing sectors. The 2120500 reflects Apollo's long-standing reputation for quality and innovation.
$234.77$277.97
Available for Purchase
Subject to factory lead times
FAQS
- Monitoring and controlling liquid level in a tank requires a level sensor or transmitter paired with a controller, PLC, or alarm system. The first decision is whether you need point level detection (knowing when the level hits a specific high or low threshold — for alarms or pump control) or continuous level measurement (knowing the actual level height at all times — for inventory tracking or closed-loop control). For point level, float switches are the simplest and most cost-effective option — a buoyant float actuates a switch when the liquid reaches a set point. Vibrating fork switches are a good alternative when the liquid is viscous or foaming. For continuous measurement, ultrasonic transmitters work well in open atmospheric tanks with clean liquids, radar transmitters handle pressurized vessels, vapors, and foam, and differential pressure transmitters are the traditional choice for high-pressure or high-temperature vessels. The level signal is sent to a PLC or controller that operates inlet/outlet valves or pump starts/stops to keep the level within the desired range.
- Level measurement technologies fall into two categories: point level (detecting when the level reaches a specific threshold — high, low, or intermediate) and continuous level (measuring the actual level height across the full range). Common point level technologies include float switches (a buoyant float actuates a switch at a set level — simple, reliable, and low-cost), vibrating fork switches (a tuning fork vibrates at its natural frequency in air and dampens when immersed in liquid), and capacitance point switches. Common continuous level technologies include ultrasonic (measures distance to the liquid surface using sound waves — non-contact, works well for open tanks), radar and guided wave radar (uses microwave pulses — handles high temperatures, pressures, and vapors), differential pressure transmitters (infer level from hydrostatic pressure — the traditional workhorse for pressurized vessels), magnetostrictive float-based systems, and capacitance/admittance transmitters. The right choice depends on the media (clean liquid, slurry, foam, solids), vessel conditions (temperature, pressure, agitation), accuracy requirements, and budget.
- A float switch uses a buoyant float attached to or enclosing a mechanical or magnetic switch mechanism. As the liquid level rises, the float rises with it; when it reaches the switch actuation point, the switch changes state (opens or closes a circuit), sending a discrete signal to the control system. Float switches are the simplest and most widely used point-level devices — they are reliable, inexpensive, require no power supply for mechanical types, and work in a wide range of liquids. Common applications include high-level and low-level alarms on storage tanks, sump pump control (turning the pump on when level rises and off when it falls), coolant reservoir monitoring, and condensate tank level switching. Limitations include susceptibility to fouling in viscous or coating liquids, and they are not suitable for applications with heavy turbulence or foam. For these challenging conditions, vibrating fork or capacitance-based switches are more appropriate.
- Both ultrasonic and radar are non-contact continuous level measurement technologies, but they perform differently in various conditions. Ultrasonic level transmitters are cost-effective and work well in atmospheric tanks with clean liquids and moderate temperatures — they are the standard choice for water and wastewater tanks, chemical storage, and open vessels. However, ultrasonic performance degrades in heavy vapor, dust, foam, and extreme temperatures because sound waves are affected by the medium they travel through. Radar (non-contact and guided wave) uses electromagnetic waves that are unaffected by temperature, pressure, vapor, or dust — making radar the better choice for pressurized vessels, high-temperature processes, tanks with heavy vapor blankets, and media that produce foam or surface turbulence. Guided wave radar (a probe that contacts the media) provides excellent accuracy and reliability in narrow vessels, still wells, and applications with low dielectric liquids. Radar instruments are typically more expensive than ultrasonic, so ultrasonic remains the preferred choice where conditions allow.
- Differential pressure (DP) level measurement uses a DP transmitter to infer the liquid level in a tank based on the hydrostatic pressure exerted by the liquid column. The transmitter measures the pressure difference between the bottom of the tank (where the liquid column creates pressure proportional to its height) and the top of the tank (the reference or vapor space pressure). Since pressure increases linearly with liquid height (P = ρ × g × h), the DP reading is directly proportional to level. DP level measurement is the traditional workhorse for pressurized and vacuum vessels where non-contact technologies may not perform well, and it remains widely used in oil and gas, chemical, pharmaceutical, and power generation applications. It is well-suited for high-temperature, high-pressure vessels and can handle a wide range of media. Limitations include the need for impulse piping (or remote diaphragm seals for corrosive or viscous media), and it requires the specific gravity of the liquid to remain relatively constant for accurate measurement.