Programming the UE One Series Hybrid Transmitter-Switches

The United Electric Controls One Series electronic pressure and temperature transmitter-switches are designed to provide transmitter, switch and gauge functions all-in-one rugged enclosure that can withstand the rigors of harsh and hazardous environments. Available in Type 4X enclosures approved for intrinsic safety, flameproof and non-incendive area classifications, these hybrid transmitter-switches have a fully adjustable set point and deadband and 0.1% repeatability. This video provides a quick tutorial on how to set up the One Series.

For more information, contact Miller Energy. Call them at 800-631-5454 or visit their web site at https://millerenergy.com.

Flow & Pressure Instrumentation for Biopharmaceuticals & Life Sciences

Producing biopharmaceuticals is one of the world’s most demanding manufacturing processes.

Brooks Instrument’s mass flow and pressure control technology helps maximize cell culture yields and control bioprocess costs. Their flow
and pressure controllers set global standards for reliability, repeatability and long-term stability.

Brooks Instrument mass flow controllers (MFCs) satisfy key biotechnology research and production requirements:

• Tight control of DO and pH during experiments and production
• NO unplanned downtime due to high cost of losing a batch or experiment
• Ability to rapidly diagnose and resolve issues with bioreactors or fermentation equipment
• Cost-effective method for adhering to regulatory requirements
• Excellent technical support and rapid response for equipment service

To read the entire Flow & Pressure Instrumentation for Biopharmaceuticals & Life Sciences guide from Brooks Instrument, download it here. Alternatively, browse the embedded document below.

Flow & Pressure Instrumentation for Biopharmaceuticals & Life Sciences from Miller Energy, Inc.

Pressure Switches - The Stalwart of Pressure Instrumentation

Pressure switch in an
explosion-proof housing.
(United Electric)

A pressure switch is an electromechanical device that detects the presence of fluid pressure and responds by opening or closing an electrical or pneumatic circuit.

In heavy industry, pressure switches are used in virtually every power plant, refinery, chemical plant, paper mill, steel mill, or other manufacturing plant that blends ingredients.

Pressure switches are simple devices. They can be broken down to their major parts: a pressure port or connection; a sensor that moves in relationship to changing pressures; an electrical or pneumatic switch that opens or closes upon movement; and finally a housing that protect the internals of the pressure switch from the ambient conditions.

Differential pressure switch.
(United Electric)

Pressure switches use a variety of sensing elements such as diaphragms, bellows, bourdon tubes, or pistons. In most cases, the movement of these sensors, caused by pressure fluctuation, is transferred to a set of electrical contacts to open or close a circuit. Normal status of a switch is the resting state. A pressure switch will be in its “normal” status when it senses low or minimum pressure. For a pressure switch, “normal” status is any fluid pressure below the trip threshold of the switch.

One of the earliest and most common designs of pressure switch was the bourdon tube pressure sensor accompanied by a mercury switch. A mercury switch is a position sensitive glass bulb containing mercury that flows over, or away from, the electrical contacts. When pressure is applied, the bourdon tube attempts to straighten, and moves enough to slightly tilt the mercury switch. Many of these kind of pressure switches were sold on steam boilers, and while they became a de facto standard, they were sensitive to vibration and breakage of the mercury bulb.

NO vs. NC electrical switch contacts.

The most common electrical switch used in pressure switches are "microswitch" type. These are also called "snap switches" because they are actuated by very little physical force, through the use of a tipping-point mechanism. These type of switches offer reliability and repeatability. They also are available in many different voltages and current ratings

One of the criteria of any pressure switch is the deadband or (reset pressure differential). This setting determines the amount of pressure change required to reset the switch to its normal state after it has tripped.  The “differential” pressure of a pressure switch should not to be confused with differential pressure switch, which actually measures the difference in pressure between two separate pressure ports.

When selecting pressure switches you must consider the electrical requirements (volts, amps, AC or DC), the area classification (hazardous, non-hazardous, general purpose, water-tight), pressure sensing range, body materials that will be exposed to ambient contaminants, and wetted materials (parts that are exposed to the process media).

It's always a good idea to discuss your application with an expert before specifying or installing a pressure switch. You'll end up saving time and money, and ensure long, safe operation.

For more information on pressure switches, contact Miller Energy by visiting https://millerenergy.com or by calling one of these numbers: In New Jersey 908-755-6700. In Pennsylvania 610-363-6200.

Use Electronic Pressure Controllers in Your Research Process Loop to Eliminate Droop, Boost, and Hysteresis

(re-blogged with permission from Brooks Instrument)

Gas pressure control is critical in many applications like life sciences and chemical/petrochemical research where flow is an integral part of the process. Brooks Instrument electronic pressure controllers can be used as they require flow to function. Compared to using a mechanical pressure regulator, electronic pressure controllers eliminate droop, boost and hysteresis, offering stable pressure control.

There are two configurations available for pressure control – upstream and downstream. This terminology is somewhat unique to Brooks Instrument electronic pressure controllers.

Downstream vs. Upstream Pressure Control

Downstream pressure controllers maintain the pressure downstream of the device itself, increasing flow to increase the pressure and decreasing flow to decrease the pressure. For this reason, this is called direct acting. This configuration is commonly called a standard pressure regulator. A downstream pressure controller acts very similar to a typical mass flow controller because they are both direct acting.

Upstream pressure controllers maintain the pressure upstream of the device itself, increasing flow to reduce the pressure and decreasing flow to increase the pressure. For this reason, this is called reverse acting. This configuration is commonly called a back pressure regulator in the industry.

Selecting and Sizing an Electronic Pressure Controller

The following information is required to select and size a Brooks Instrument electronic pressure controller:

• Process gas
• Maximum flow rate being used to maintain pressure -The “sweet spot” for pressure control is between 100 SCCM and 5 SLPM.
• Calibration pressure (maximum pressure to be controlled)
• Reference pressure (for upstream controllers the reference pressure is the downstream pressure and for downstream controllers the reference pressure is the upstream pressure)

As long as flow is present in a process you will typically find the need for some type of pressure control. Vessel sizes up to 30 liters commonly use flow rates up to 3 SLPM during their process steps. Brooks Instrument pressure controllers are a perfect fit for these services, offering stable pressure control with no droop, boost or hysteresis, which are commonly experienced when using a mechanical pressure regulator.

Typical Bioreactor Process Using an Upstream Pressure Controller