Ask An Expert

Nema 4 enclosures provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dusty, to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow, splashing water, and hose directed water), and that will be undamaged by the external formation of ice on the enclosure. The only difference between NEMA 4 and NEMA 4X enclosures is that NEMA 4X enclosures offer corrosion resistance.

To figure out the cable ampacity needed for your "genset" installation, you need to figure out the ampacity per phase for the unit. For this example we will use a standard generator configuration which will guide you along the lines of proper cable sizing. Example: Your company has sized the genset for the customers application and arrived at a Three Phase AC Power, 250 kW running at 480v. Take these numbers and plug them into the formula below. (kW x 1000) / (Volts x PF x 1.732) (PF is the Power Factor and is the ratio of kW to kVA) (1.732 is the square root of three and is required to get the amps per phase) (250 x 1000) / (480 x .80 x 1.732)= 376 amps per phase Now that you know the amps per phase to be 376 amps. Youll need a cable to handle the A, B, C, and Neutral connections. If you choose to use one cable per phase, you would need to use a cable larger than 376 amps. If you look at 600V Portable Power cable you will see that 4/0 AWG size cable will handle 405 amps. This would be the cable of choice.

ABB's MNS-MCC is a new concept in NEMA motor control centers. The ABB MNS-MCC represents the next step in the advancement of motor control centers. While using the long established dimensions of the North American NEMA market, the MNS-MCC offers benefits never before available in traditional motor control centers including: - Closed door removal and insertion of units - Touch safe design throughout - Use of multifunction separator to segregate vertical bus and passively establish a fault free zone - Faster maintenance thanks to withdrawable technology - No tools required to change out units - Closed door removal and insertion - Pull apart terminal blocks for control and power wiring - Viewports to allow visual inspection of all bus splices

We recommend using Rittal's Therm calculation program. The laborious calculation of the climate control requirement is assumed completely by the Therm software. In the form of documentation, you receive: - The enclosure surface area calculated - The radiation level discharged into the environment or absorbed externally - The resulting degree of cooling required - The internal enclosure temperature without cooling measures and lastly a proposal of possible alternatives for solving your specific enclosure climate control problem. You decide which solution is optimal. You can also use the formula below to determine the required cooling capacity needed to maintain the desired operating temperature for your enclosure.This selection procedure applies to uninsulated, sealed, gasketed enclosures in indoor locations. (WATTS x 3.413)+ [1.25 x AREA (ft2) x T(F)]/(BTU/HR) Call us for more information.

Hubs transmit all data out all connected ports. Switches automatically learn the network layout and then only transmit data where it needs to go, making the network more efficient. Managed switches add an additional level of configuration and monitoring capability to a network.

Applications like warehouses, distribution centers, production facilities and other industrial spaces with occupancy less than 50% and with high ceilings (15 45 ft) are ideal candidates for sensors. Lit by high bay fluorescent or HID fixtures, high bay lights draw significant energy and often burn when the space is empty or unused. Whats more, because most facilities dont have the ability to control their lighting, these fixtures continue to stay lit and waste energy and money, even when the space is unoccupied. Occupancy sensors save energy and money by delivering light only where you need it, when you need it. Consider a large warehouse with many long rows of racks/shelves loaded with merchandise. A pick order is issued, the picker identifies the aisle and drives a forklift truck into the space to pick the appropriate order. If no sensors are in use, the entire area is lit before and after the picker enters the space even if there is no one else in that area. This wastes energy and contributes to higher costs. Now, with high-bay occupancy sensors, the sensors will see the movement of the approaching forklift and turn on the lights only where there is movement or occupancy significantly reducing energy consumption and costs. Sensors coverage patterns are broad enough to identify movement and turn on the lights well before the forklift enters the space. Plus, with the programmable timer, the lights will again be turned off after a set period of inactivity usually 10 15 minutes. This is just one example of how occupancy sensors can cut costs and reduce energy consumption.

The model of the panel and breakers would be helpful

Pursley went out of business several years ago.