The Mamco LF10 H series pressure switches are rugged and reliable devices designed for air systems applications and electrically driven compressors where the pressure needs to be maintained between two preset values.

The LF10 H series are equipped with a unloader valve that prevents the compressor from starting under load. Mamco offers an optional four port manifold which provides easy installation of relief valves, gauges and other accessories.

These switches are commonly found in OEM applications and are also available as a direct replacement for many brands. They can be used on systems with operating pressures reaching 175 PSI. They are double pole double throw and are electrically rated to switch up to 3 HP.

Mamco offers a variety of different pressure connections, valve connections, and valve types.

• Corrosion Resistant and Non Metallic Cover
• No Wire Looping
• Visible Contact
• No Drift Pressure Setting
• Captive Cover Screw
• Ample Wiring Room
• 2 Ground Screw
• Easy to Adjust
• Automatic Unloader Valve Available
• Pulsation Dampener Standard

The Air Spring Insulator BiAir^® consists of a cast steel or aluminum housing, within which the air space is contained by thin-walled flexible and pressure-resistant rolling membrane. A piston sits on top of the membrane and is pressed into the air space. This design allows a highly-effective isolation of vibration. In order to simultaneously achieve a high degree of damping, the air space is divided into two chambers connected with an air tube. (load/damping volume) A choke valve can be used to adjust from outside the cross-section of air flowing into the connecting tube from outside according to the degree of damping required. The friction on the flow of air caused by the choke valve can create a damping effect of up to 20%. Damage to the rolling membrane caused by overpressure is prevented by additional safety valves.

Range of Applications

Highly-effective isolation of vibration for sensitive measurement and testing equipment, precise finishing machines, laser equipment and optical and electronic instruments. Another important application is the vibration-insulated mounting of test benches for the motor vehicle, transmission and other industries. BiAir® Air Spring Insulators provide excellent isolation of foundation and equivalent machine loads.

Advantages over Conventional Steel Springs

BiAir® Air Spring Insulators with level control provide active isolation. The correct level of machines and foundations is maintained constantly! Level control and adjustment is conducted automatically! Furthermore, changes in load result in appropriate adjustments to the air pressure in the air springs such that the required isolation remains constantly effectively despite changes in load.

Bilz Leveling Systems

Air springs are available for greater maximal loads and lower natural frequency. Level control provides an important contribution toward the optimal function of an air spring system. If a change in load likely occurs on equipment mounted with an air spring system, such that compression of one of the springs or an inclination of the equipment will result, a leveling system might be the only solution available. The change in air pressure in the air spring insulators adjusts the height of the individual elements (BiAir® or FAEBI®). By quickly pressurizing or de-pressurizing the springs, the proper level can be maintained despite variations in the position of the load.

Control System

The leveling system consists of at least three air springs. Even if several insulators are required for design or load reasons, three control groups are necessary in order to avoid a statically over-determined system. In such a case, multiple air springs are grouped together and controlled in parallel.

BiAir® Mechanical Pneumatic Control Valves

One simple, but effective solution is the mechanical pneumatic proportional valve. A small plunger is used to continually check the level. The plunger position is transmitted to the push valve. In accordance with the position, the air spring will be pumped up with or relieved of pressure. The level can be maintained constantly to within ± 1/10 mm. There are three control valves working together with an air compressor which limit system pressure to a maximum of 6 bar, remove any accumulated condensation and cleanse the system air of solid particulates such as rust and dust.

BiAir® Electro-pneumatic Level Control Important Advantages of Bilz Level Control are:

• The high degree of re-set accuracy and of level maintenance of ± 1/100 mm
• The extraordinarily fast response time
• The possibility of adjusting the speed of the system (amplification and re-set time) optimally with regard to the specific conditions. (control loop)
• The robust proportional valve with large air volume flow
• The exceptional ease of use

System Components

Each system is comprised of 3 position sensors, 3 electro-pneumatic proportional valves, a control unit (digital processor) and a compressor. The electro-pneumatic control meets the most strenuous demands. It is primarily used when high re-set precision and extremely short response times are necessary. Very accurate position sensors are used to measure the deviation between real position and nominal position of the air spring insulators to within 1/100 mm. The control unit processes the electronic signals and determines the extent to which the springs are either pressurized or de-pressurized via the electro-pneumatic proportional valve.

Control Unit

The control unit consists of a printed circuit board containing the entire logic circuitry of the three control loops, the three air pressure displays, setting screws for the adjustment of the machine and nominal speed, and a switch allowing the operator to completely de-pressurize the air springs. The control unit is also available as a 19-inch rack component or with its own case.

Software

A special software package is also available which allows the operator to set and optimize nominal values, to log setting parameters and to conduct error diagnostics. The integrated interface also enables the operator to connect to the computers of the machines to be isolated allowing him to manage a wide range of diverse operating modes.

A typical compressed air system will lose compressed air through pipe connections, non-demand drains etc. At the end of the final work shift, the Air-Saver will shut the air tank off from the rest of the system. The content of compressed air within the air tank will be saved rather than lost through pipe leakages. The Air-Saver is installed on the air outlet of the air tank. The Air-Saver will automatically open just prior to the working shift begins, and closes just after the working shift is over.

Features:

• Slow valve opening to avoid water hammer in pipe line system
• Time programmed or remote controlled
• Built-in quartz controlled timer
• Integral lithium battery protects program for five (5) years
• Current time display
• Each individual day can be programmed according to specific working day shift requirements
• Reset Function
• External push button controls (disassembly not necessary)
• Easy to program
• FPM seals
• Orifice 1 or 2 inch
• Manual valve opening and closing possible, in case of a power failure
• Fully automatic- maintenance free
• Easy to obtain air in case of overtime work
• Integral Lithium battery protecting the program
• Micro-Processor controlled (multi cycle 7 day program)
• Large LCD display showing program cycle and current time
• Compact design -Easy to install
• User friendly control panel - Simple to program
• Remote switching kit available

Benefits:

• No unnecessarily start up of compressors during periods when compressed air is not required.
• At least one air receiver's worth of compressed air savings per day.
• Possibility to shut of parts of the pipe line system where compressed air is not needed continuously.
• Manual Override: Yes

Remote Compressor Operation & Tank Level Monitoring - SITEMASTER SYSTEM / SITECOMMANDER SOFTWARE from Visicomm Industries.

Industry: A Multi-Site Interstate Tank Farm Operation Problem: Illinois company had remote tank site locations and was unable to percolate product and monitor levels in the tanks. Each site consists of 5 to 8 large 100,000 to 500,000 gallon tanks and there are a total of 14 such sites located at remote railroad sidings scattered over 14 mid-western and western states. The product in each tank must have air bubbled thru it for one hour out of every 48 hours.

This arrangement requires an attendant to visit the site, check the level of the tanks and manually start the compressor (at those sites without an electric motor driven compressor) and open then close the valve for each tank. The object is to automate the aeration at each of the 14 sites with the Sitemaster (confirming that it is actually accomplished on the automatic schedule by telephone with printout to the Site Commander) and be able to monitor the site for any problems, as well as determine the tank levels from the central office LAN in Illinois and from any laptop computer by personnel on the road.

Solution: Provide a Sitemaster Model 16RM8A10R for each site to allow remote compressor operation and tank level monitoring. Provide a Sitemaster Model 16RM8A10R unit (with all accessory valves, level controls, connection diagrams etc. to make a complete system) for each remote site and equip the central office LAN (which has a DSL connection to the internet) in Illinois with the internet enabled Sitecommander Software. The software runs on a dedicated computer on their LAN and has a dedicated dial-in phone line used by the remote site phones (it is separate from their phone system, will not rollover, will not be picked up by an answering machine etc.-and is $12/mo. dial-in, not an expensive leased line or DSL-T1 connection which could, of course, also be used for continuous real-time control and data available on site).

This computer hosts the Sitecommander Software and access to it is protected by their firewall making it virtually impossible to hack--the general public cannot gain access to the LAN (as opposed to an internet website which is open to all comers on the web), and if a hacker did, he would need a copy of the Sitemaster software pre-installed on his computer to see anything. Visicomm Industries will refer to this computer as the Host from now on. Anyone in the central office on the LAN has level 1 access to the host (and other levels, if authorized). Any personnel on the road with a laptop (that has the Sitemaster software pre-loaded) can go to his internet service provider and our software will send an IP address which will allow pre-authorized passage (using a combination of three of the 64000 ports--very difficult for a hacker to discover, and if ever breached, then without the software it becomes almost impossible to see anything at all) thru the firewall and access to the host.

The Sitecommander Software (which can handle up to 200 sites) can be programmed to dial out and poll each site as often per day as needed. In this case, it was decided to poll and update the tank levels (for inventory indication) at 8am, 12noon and 6pm and post complete status of each site to the level one database for all to see. Those with level 2 access could go directly to the site and view the real time status of any site.

Each Sitemaster 16RM8A10R monitors up to 16 (more with add on cards- see below) normally open/normally closed alarm contacts such as a thermostat, pressure sensor, magnetic door contacts, valve position proximity switches etc., and has 10 form A relay contacts that can be programmed to act in conjunction with any monitored device--thus if A happens then a relay turns B on and C off (or if A and D happen, then turn B and C on) etc. It also has the ability to accept up to 8 analog signals (4-20ma, 1-5V) which in this case are connected to the ultrasonic level sensors in up to 7 of the tanks with the eighth used to indicate outside air temperature at the site (of course, the analog signals could be used for pressure, voltage, amperage etc. sensors).

In this case, the Sitemaster was set up to monitor the levels of 1 to 7 tanks at each site with readouts in feet, auto-calculated gallons and tons with each site being polled at 8am, 12noon and 6pm with details stored in the database which is available to everyone on the main office LAN. In the event of an alarm on any monitored point, a fax detailing the nameplate of that problem (such as no air in a particular tank at a time when it is scheduled to be there) is sent to the main office (if night time alarms must be handled, a pager could also be called-alerting the recipient to get on his laptop and see what it is).

There are three levels of access controlled by user name, password and authorized level: Level One Access - Available to anyone on the LAN with a copy of the software pre-installed on his/her computer. This level can look at Site Status only which includes any data posted at the last update time(8-12-6pm) and any alarms posted since. No changes allowed. Level Two Access - Can click on any remote site as shown on the Site Status page and dialout to the remote Sitemaster 16RM8A10C unit for real time status only. This assumes, of course that someone else is not on the outgoing to site/incoming line from site line assigned to the Host. No changes allowed. Level Three Access - For access to the control section. Entry to this section is recorded by time, date and access code. This allows changes to the site settings, functions as well as real time control.

The Sitecommander software and its host can handle up to 200 separate sites per system and each Sitemaster comes with the possibility of add on boards for a total of up to 224 digital inputs/outputs (for example 124 inputs and 100 outputs etc.) and up to 72 analog inputs per site. Our standard NX--B Annunciator/Monitors can also be integrated into each site if a local audio-visual alarm is needed for those times when an attendant is present.

The ultrasonic level control transducers furnished by Visicomm, as part of their system responsibility for this particular application, are weather proof, unaffected by condensation, totally sealed and suitable for use with any liquid (not solids because of lack of a level surface to sense). Certified Class 1, Div.1 explosion proof sensors are available. Our system allows for a maximum of 72 tanks per site at each of up to 200 sites located anywhere there is a 120VAC outlet and a phone line available (including a cell phone line if need be).

As part of their system design responsibility, Visicomm also furnished a diesel engine startup and monitoring system (for some sites) and an electrically actuated stainless steel ball valve with pressure sensor (in line after each ball valve to confirm pressure) for each tank. The photo above shows a battery charger/power supply (bottom of relay rack) with battery (which provides 4 hours of operation in the event of a power outage), above which there are 5 manual bypass switches with led's to allow manual operation when personnel are present. Just below these switches there is a port for connection of a laptop. When on site, personnel can manually bypass the computer control and operate the site or they can use a laptop on site to take control. The top of the relay rack is occupied by the level control system LCD display and controls.

At another customers request, Visicomm is looking into the possibility of being able to switch on a scanning camcorder at each remote site for a look around and transmitting the sight and sound over the dial-up connection before sending someone to the site to investigate a problem--not yet available as of 7/02.

The Environics® Nitrogen Air Generator (NAG) uses membrane technology to separate and recover nitrogen from compressed air. Atmospheric air is 78% nitrogen, 21% oxygen and 1% other gases. The NAG uses the principle of selective permeation to produce high purity nitrogen. The Nitrogen Air Generator has been designed to deliver OSHA grade breathing air and 98% pure nitrogen. The system will deliver a maximum flow of 30 LPM nitrogen at 50 psig and 95 LPM air at 50 psig. The pressure outputs for both air and nitrogen are adjustable.

The NAG has been built into two shipping containers to withstand the rigors of multiple shipments. Each container is equipped with 4 casters for ease of movement. One container holds the compressor, water separating and air cooling components and the second box holds the filtration, storage containers and pressure regulating components for both the nitrogen and air output gases. The containers are manufactured to either sit next to each other or mount on top of each other to save floor space. The units have been designed to meet a maximum noise specification of 65 dB(A) and can be run in an office or laboratory environment. The actual covers of the container are mounted on slides and when extended become part of the sound baffling system. The maximum operating ambient temperature for the NAG is 90 degrees F.

Membrane technology is industry proven, safe and reliable. Membranes are simple, passive devices that require no maintenance.

The compressor that is used is a 3 HP oil-less scroll compressor that only needs maintenance every 10,000 hours of use. The rotary design of the scroll compressor permits a continuous 100% duty cycle. Other standard features of the Environics nitrogen/air generator include: a Magnetic Starter, Motor Overload protection, a high temperature shutdown switch, an air cooled after cooler and a single phase motor.

Leviton's has expanded its line of Power Switch™ Industrial Grade Switches with the addition of a new line of Safety Disconnect Switches. The line of Power Switch Industrial Grade Switches previously consisted of Motor Starter Switches (MSS) in 30, 40, and 60 Amp ratings and now also includes Safety Disconnect Switches in an IP65 Watertight 30 Amp Non-Fused Model and IP67 Watertight Non-Fused models in 60 and 100 Amp with Fused models in 30 and 60 Amp. Leviton's MSS Series Motor Starter Switches in metal NEMA 1 and NEMA 3R enclosures are suitable for a wide range of industrial MRO and OEM applications, including manual ON/OFF switching control of conveyor lines, machinery, air compressors, heaters, and other heavy manufacturing equipment. They are high priority, "Class A" inventory items ideal for well-equipped electrical maintenance shops. The new line of Safety Disconnect Switches (SDS) safeguards users by preventing the haphazard making/breaking "under load" of electrical connections. The compact 30 Amp non-fused model is ideal for tight spaces and smaller equipment lines. For safer servicing, the 30 Amp model's high visibility red handle can be locked and tagged in the OFF position, even when the cover is off. Fused models feature integrated, "finger-safe" fuse holders accepting "Class J" Time-Delay fuses. All Power Switch SDS's are supplied with 1 factory-installed auxiliary contact for remote line management and power monitoring. Space is provided for an additional auxiliary contact, maximizing the device's utility. The IP67 Watertight Disconnect Switches include a red "pistol grip" handle with integrated lockout that meets OSHA safety regulations and provides visual confirmation of the switch's status. For faster installation, SDS's feature generous wiring space and are supplied with pre-wired grounding plates connected to the factory-installed Liquid-tight hubs. A Leviton exclusive, the rugged bottom hinge mechanism pivots 180 degrees for easy access during installation and maintenance. Contact Leviton Manufacturing Company, 59-25 Little Neck Parkway, Little Neck, NY 11362, www.leviton.com.