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- The Cerus Industrial team

BAS Locking Mechanisms- Revolutionizing the HVAC market one starter at a time!

 

A very nice feature of our BAS starter is our lockable cover and lockable handles on the BAS combination models.  These features are taking added significance as the BAS continues to revolutionize the HVAC starter market.  Before the BAS starter contractors and engineers were forced to specify and use starters primarily designed for installation for irrigation and pumps. These starters were designed for outdoor use and, even worse, were designed for thermal overloads and fused disconnects that, while cheap to manufacture, require the user to open the panel to change fuses and reset the thermal overload (or replace). Understandably for safety, a locking mechanism is important for this type of starter. This locking mechanism also provides a lock-out mechanism for service work.

 

With the BAS, there are no fuses to replace-  the electronic overload is trouble-free and resets if necessary, safely and automatically. Specifically engineered for HVAC applications, it is designed to operate for years without user intervention. This is reflected in our case design- It is engineered with a screw cover and tamper lock since once it is mounted and commissioned there is little reason to open the cover. When ordered as a combination unit, the breaker is lockable, primarily to allow the user to safely tag out the starter for servicing the motor. Of course all of these features go above and beyond what is required for UL, the National Electrical Code and NEMA.

 

So don’t be afraid to have the discussion with your Engineers and Contractors- Yes we have no bulky interlocking mechanism. We have a locking cover and a lockable breaker which meets and exceeds UL, NEC and NEMA requirements. Our starters are designed for integration in modern, commercial buildings and specifically engineered for HVAC control applications. They are not engineered for servicing old technology and for installation in the middle of a corn field!

 

As always our team is here to help you. We have not met a specification yet which the BAS starter does not meet or exceed the requirements.

 

CERUS INDUSTRIAL DEVELOPS SMART STARTER FOR BUILDING AUTOMATION

 

Beaverton, OR: Cerus Industrial, a leader in motor controls for the building automation industry, introduced their intelligent Building Automation Starter (BAS) with BACnet communication for building control systems.

 

        “This new starter fills the demand in the market for better control and better energy savings of small motors used with building control systems,” said Andre Perra, President of Cerus Industrial. “A typical installation of our new BAS starter will save an end user $100 to $300 per year with better control, efficiency and maintenance. It’s also easier to integrate over conventional motor starters with direct communication to a building control system. That saves $100 to $200 per unit by eliminating extra peripheral control and monitoring devices.”

 

        In almost every project where building control systems are used, there are simple on / off motor starters used to control small fans and pumps in a building. Unlike larger motors which run under variable speed for energy savings, smaller motors (1 to 5 hp) typically run at 100% speed. The energy savings are realized through centralized control and monitoring of the motor with a building automation system. With conventional starters, building management systems must control and monitor the drive by using relays and sensors that must be installed in addition to the starter.

 

        The BAS starter is designed specifically for building automation applications and as such, comes complete with built-in sensors and monitors required for building automation systems. It also has the added benefit of a single point of communication and control through BACnet communication, the preferred protocol for building automation systems. Monitoring is integrated into the intelligence of the starter, providing important supervisory and maintenance information. Damper and actuator control functions also reduce control points on the building management system, improving throughput and performance while reducing installed cost.

 

        The BAS starter is available from ¼ HP to 300 HP, and is sold exclusively through Cerus Industrial’s Dealer Network.

 

        If you would like more information about this topic, or to schedule an interview with Andre Perra, please contact Liz Noxon at 503-906-1217 or by email at liz.noxon@cerusindustrial.com.

                                                                                                                                                -More-

 

About Cerus Industrial

 

        Cerus Industrial is a leader in the manufacturing of motor controls for HVAC and Industrial markets. Cerus’ products include variable speed drives, building automation starters, soft starters, motor control components and related accessories.

 

        Founded in 2003, Cerus Industrial has grown rapidly and sells nationwide through their authorized dealers and distributors. Cerus Industrial’s management team is comprised of industry veterans in the motor control field who have successfully founded other companies in the building control industry, such as Veris Industries.

 

-End-

 

 

                

Interrupting Ratings and Short Circuit Current Ratings[1]

The 2005 National Electrical Code (NEC) [Article 409.110] addressed the need to accurately identify and label an industrial control panel’s Short Circuit Current Rating (SCCR). This requirement is necessary to ensure the integrity of the panel and the safety of personnel during a short circuit situation.

The NEC also requires an SCCR for:

• Industrial machinery electrical panels [Article 670]
• Multiple motor HVAC equipment [Article 440]
• Meter disconnect switches [Article 230]
• Multiple motor controllers [Article 430]

Article 409 was added due to the dangerous and common misconception by equipment manufacturers that the circuit breaker’s interrupting capacity or the fuse’s interrupting rating in the panel’s feeder circuit is also the panel’s SCCR. In reality, the panel’s SCCR is directly related to the current-limiting capabilities (opening time) of the protective device in the feeder circuit and the individual panel components’ SCCR. In most cases, a panel’s SCCR is less than the interrupting capacity or interrupting rating of the overcurrent device.

 

Installation considerations

Also, keep in mind that an existing panel being moved to a new location within a facility still requires verification that its SCCR is greater than the new available fault current. As the panel is moved closer to the electrical service, the available fault current can increase, and the panel needs to withstand this new level. Even if the panel isn’t moved and the available fault current increases from the utility company, this verification needs to be done to ensure a safe environment.

 

How is a panel’s SCCR determined?

NEC Article 409.110(3) states that the SCCR shall be based on a listed (i.e. UL tested) assembly or an approved method of calculation.

 

Since this NEC rule in 2005, Cerus has been working with UL to verify all of our drives, starters and control panels carry a UL approved SCCR rating. For example, Cerus Drives are rated for up to 100,000 ampere interrupting capacity when installed with a UL approved breaker. A Cerus BAS combination starter exclusively uses Cerus UL tested and approved components that provide a UL rated SCCR of up to 100,000 amperes.

 

For more information, or concerns about interrupting ratings for your particular installation, please contact our knowledgeable Cerus sales representative who will be happy to answer your questions.

 

Electronic Coils on CRC 100 – CRC 800

One of the best features of the CRC 100 – 800 contactors are the standard electronic coils. The electronic coil provides dramatic improvement in operation over standard coils, offering an extremely wide operating voltage range and a very low consumption for the size of the contactor. For example, a typical 400 Amp contactor with a 120 volt coil will draw over 1 amp on inrush and holding current of 30 to 40 milliamps. With our electronic coil in a comparable size the inrush is only 393 milliamps and holding current is less than 15 milliamps. This will save significantly in sizing power transformers for the coil. Additionally the electronic coil has an extremely wide range of operation- for the 120Volt example above the coil is actually a 100 – 200 Volt coil with a AC or DC operation!

In addition to these performance improvements over standard coils, the electronic coils offer one other operational improvement: Jam Protection. This feature shuts off the coil current in the event of a mechanical jam within the contactor. This prevents the coil from overheating and potentially catching fire- a real possibility with larger contactor coils, particularly on standard coils that draw over 1 amp! In normal operation most users will not ever see this feature in operation. However, when the electronic coils are used with mechanical interlocks, the jam feature may prevent smooth operation if there is not sufficient overlap between the opening and closing of the two contactors. If you plan to use our 100 amp or larger contactors with a mechanical interlock, contact your Cerus representative for application recommendations.

 

Cerus electronic coils for CRC-100 -800:

• Wide range and easy to apply.
• Low current consumption for energy and cost savings.
• Jam protection for safety.

 

We make it easy!

Basic Float control pump package or advanced pump package?

                If you are working on pump systems with float control, Cerus has two duplex alternatives: basic and advanced.  So, when should you use a basic package and when should you use an advanced? Generally speaking the basic system is just that- basic with no intelligence built in. It is great for cost sensitive projects or for temporary installations. The advanced system includes our state of the art PLC with intelligence and flexibility to suit almost all applications. Additionally the advanced package includes our electronic overload and manual motor starters for both branch and motor protection, while the basic includes our thermal overloads with differential phase failure protection. So the advanced package is great for maximum protection and application flexibility.  The summary table below details the key differences between both packages. Still not sure? Give us a call and we will be happy to determine the best package for your application.

Feature	Basic	Advanced
Float Control	4 Floats	3, 4 or 5 Floats selectable
Alternation	Manual by switch or optional alternating relay	Automatic
Motor Protection	Differential Thermal Overload	Wide range electronic overload with phase failure protection along with MMS for branch circuit protection
Control Voltage	120 VAC standard, 24 VAC optional	24 VAC standard
Lag pump start / stop delay	Not available	Standard, adjustable
Hand / Off / Auto Switch	Standard	Standard
High Level alarm and alarm contact	Standard	Standard
Run Light	Standard	Standard
Automatic Fail pump switch	Standard	Standard
Horn	Optional	Optional
Run Hour Meter	Optional	Optional
Broken wire or bad float detection	Not Available	Standard
Float input filter to eliminate noise or float bounce issues	Not Available	Standard

 

 

Tech Tip: Pilot Devices-

 

There are many sources of Pilot Devices available in the market. When specifying or purchasing pilot devices here are some key design and construction details you should look for in industrial applications:

 

• Double screw metal mounting bracket. This is the most structurally sound way to mount your pilot devices on a operator panel. Pilot devices that use single screw or plastic clamp are prone to slip or loosen over time.
• Screw in contact blocks. While clip in blocks are great assembly time savers, they are much less secure and can easily be knocked off inadvertently or pop off in extreme conditions.
• Contact blocks rated for at least 1 million operations.
• Tough metal bezel for pilot heads. The metal bezel stands up to a high amount of abuse and protects the switching mechanism from bumps and blows from operators and their equipment.
• Vibration and shock resistance up to 200 times the force of gravity.
• Up to 600 VAC contact ratings.
• UL, CSA and IEC ratings. Tested to NEMA standards.

 

Of course Cerus Pilot Devices meet or exceed all of these criteria. If you are using Pilot Devices in an industrial application, contact your Cerus representative for your free sample.

Save Valuable Panel Space with New Mira Contactors:

 

With our new Mira Contactors you now have at your disposal a world class solution for group motor controls. Mira contactors combined with our MMS solve four main issues associated with a group motor control panel:

 

1. Group Motor Protection: Our MMS carry a UL (Type E) group motor rating allowing you to install multiple motor circuits from one large feeder circuit breaker or fuse (up to 1000amp rating). In traditional motor control panels without this special UL listing you are forced to supply supplemental branch circuit protection for each motor load. With our MMS certified as UL Type E, individual branch circuit protection and overload protection for connected motors is built into the MMS. Therefore supplemental protection is not required for your individual motor branches, allowing the panel to be fed directly from a larger feeder breaker saving you hundreds, or even thousands of dollars per panel.
2. UL Coordinated Short Circuit Rating:  Add our new Mira contactors in combination with our MMS and the interrupting rating of the MMS applies to the combination circuit. This is another special category certified by UL under UL 508 and is called Type F. Type F circuit breakers (like our MMS) are specially tested for a coordinated interrupting rating by UL for motor loads. This provides your motor control panel with a high interrupting rating (up to 65KAIC) without additional fusing
3. Panel Space:  In addition to the money saving UL ratings, the Mira contactor and MMS save valuable panel space. When the Mira contactor, MMS and matching back-plate and connecting pieces are used, you create one slim combination starter assembly ready for DIN rail or screw mounting.  When mounted the assemblies take less than half the space of traditional combination starters.
4. Assembly Time:  Use the backplates, connecting pieces, and busbars and a group motor installation using Mira and MMS take minutes to assemble instead of hours.

IEC vs. NEMA Contactor Ratings:

Part 1 Normal duty

 

Many customers ask for us to explain the difference between NEMA sizing and IEC sized contactors and starters, and how a dual rated IEC and NEMA contactor or starter compares with a NEMA only equivalent. In this two part tech tip we will explain how to size both NEMA and IEC size contactors, and how they differ in performance.

IEC ratings for contactors are sized based on application and motor ratings. For AC motors there are four utilization categories:

 

AC1- Resistive loads such as heaters with a power factor greater than .95

 

AC2- Starting, plugging, inching and jogging of slip ring motors.

 

AC3- Line starting and breaking during normal running of standard squirrel cage inductive motors. Application examples include lifts, conveyers, pumps, fans etc. This is considered ‘normal’ duty for AC motors.

 

AC4- Plugging, inching and jogging of squirrel cage and slip ring motors. Application examples include cranes, hoists, printing machines, etc.

 

IEC contactors are sized precisely based on one of the AC utilization ratings noted above. Normal duty or the AC3 rating is typically used for sizing the contactor. For example a 32 amp IEC contactor like our CRC 32 is rated for 32 amps full load current at 220 to 460VAC in AC3 applications. To size the contactor properly you will need to know the voltage, current and HP and use the appropriate AC rating.

 

NEMA contactors are similarly rated for general purpose line starting and breaking during running for standard squirrel cage motors. The major difference is that the NEMA ratings are broader and have a small amount of margin built into the ratings to cover the broader range. NEMA starters are rated by size: 00, 0, 1, 2, 3, 4, 5, 6 and 7. To size the contactor you need to know only HP and voltage.

 

At Cerus we dual rate our contactors for both NEMA and IEC ratings. Our NEMA rated contactors meet the NEMA sizing requirements and the IEC ratings for that particular size contactor. Using our CRC 32 as an example once more, we see it is also rated as a NEMA Size 1 contactor. To size a dual rated contactor like our CRC 32 you will need HP, voltage and current (current is needed to insure that the motor FLA does not exceed the contactor AC3 rating since this is a design limitation).

 

In summary, for dual rated or IEC rated contactors you will need to size a contactor or starter based on HP, voltage and current, while a NEMA contactor or starter is sized only by voltage and HP. For general duty applications (AC3), Cerus CRC contactors that are dual NEMA and IEC rated, have similar or superior performance to NEMA only contactors. Next time we will look at how the two compare in heavy duty AC4 applications with a large amount of plugging, inching or jogging.

NEMA vs. IEC contactors Part 2:

Heavy duty applications

 

Last time we looked at how NEMA and IEC contactors differ in sizing for general applications. This time we will look at the differences in applications which require plugging, inching and jogging, or AC4 utilization category as defined by IEC. As a reminder there are four main utilization categories for IEC contactors:

 

AC1- Resistive loads such as heaters with a power factor greater than .95

 

AC2- Starting, plugging, inching and jogging of slip ring motors.

 

AC3- Line starting and breaking during normal running of standard squirrel cage inductive motors. Application examples include lifts, conveyers, pumps, fans etc. This is considered ‘normal’ duty for AC motors.

 

AC4- Starting, plugging, inching and jogging of squirrel cage and slip ring motors. Application examples include cranes, hoists, printing machines, etc.

 

NEMA and IEC have normal duty ratings for contactors that follow AC3 utilizations as we talked last time. For AC4 use, both NEMA and IEC will require a derating.

 

NEMA sizing for plugging inching and jogging follows a standard sizing table. This table results in approximately a 20 to 70% derating compared with normal duty. This table does not specify, nor does it require a life cycle rating be published. So while a NEMA contactor may perform at this derating level, the impact on life cycle ratings is dependent on the manufacturer.

 

IEC deratings for AC4 depend on life-cycle ratings the end user wishes to maintain. With our CRC 32 as an example (which is also rated as a NEMA Size 1 contactor), the NEMA derating table will derate the contactor 50% at 460 volts. Using this NEMA derating for the contactor, the lifecycle rating for the contactor will also reduce to 10% of the AC3 rating.

 

It is difficult to compare NEMA contactors and IEC contactors for AC4 utilization, since NEMA life cycle ratings are usually unpublished information and is dependent on the manufacturer. In general though, the IEC rated contactor will need to be sized more carefully when used in AC4 applications than a NEMA only contactor. In both cases life cycles will be reduced and if a higher lifecycle is needed, then the contactor sizing will need to be derated further, or a higher size contactor will need to be selected to maintain the lifecycle rating and load rating desired.

 

This is probably the biggest area of misapplication when NEMA customers switch to IEC style starters. Lifecycle curves are available in our technical publications for contactors which can assist you in making the right selection for your application (insert weblink). A good rule of thumb with our CRC series contactors for AC4 applications is to use a contactor 2 to 3 times higher than the load rating at AC3 to have a similar life cycle rating. Or simply call us at Cerus to find the right size- NEMA or IEC!

Tech Tip: BAS Starters for Indoor Air Handlers

 

If you regularly order and quote indoor air handlers this tech tip will help you improve your competitiveness and reduce long term operating costs.  The most popular indoor air handlers offer an option for a built in starter. When this option is selected, you will receive a thermal overload starter for an additional price of approximately $1000. Mounted in the access door area it reduces the access door from 30 to 12 1/4”, making field replacements of belts, pulleys etc. a challenging task.

 

Instead, on your next indoor air handler, use a BAS starter. Simply order the air handler field mount ready for the starter (this usually is a factory option of $175). A BAS starter can then be mounted outside the air handler keeping the access door free and clear. The net result is your customer gets a superior starter with electronic overload protection, a five year warranty and reduced long term operating costs. You save several hundred dollars on the package, making you more competitive — a true win-win!

 

Indoor Air Handler Built in Starter or BAS?

	Built in Starter	BAS
Overload Protection	Thermal	Electronic
Jam Protection	Per thermal curve (typically 10 seconds)	Included, trip in 3 seconds.
Phase fail protection	Slow usually 30 to 1 min	Included, trip in 3 seconds
Direct Digital Control	Requires interposing relay	Direct wire
Warranty	One year	Five years
Operating costs	Access door limit increases long term maintenance costs	Access door unimpeded for lower maintenance costs.
Installation costs	Pre Installed	Electrician 50- $100.
Starter Cost	$1000+	List price $575 +$175 field mount option on air handler
Total Savings		$200 to $300