Tutorial
adapters that will allow the existing wiring arms to be attached to the new input/output (I/O) cards. An example of this is the Schneider Electric 984 to Quantumâ„¢ conversion kit shown in Figure 2. This method keeps the existing panel wiring intact and prevents errors from rewiring existing panels. It also removes the need to do complete panel replacements. Sometimes the migration can be staged. For instance, the processor can be changed to a newer model, and then the I/O cards changed later, allowing municipalities to extend the migration overtime and accomplish it within the limits of the maintenance budget. Replacement of existing switchgear and motor control centers can be expensive, and the hidden challenge of moving or rewiring field wiring and relocating conduit stubs is often overlooked. Sometimes this can mean removal of concrete. Replacement of power equipment takes a long time, and in a water and wastewater facility, some means must be found to keep the systems up and running while the replacement occurs. Obviously, it would be beneficial to be able to upgrade these older systems to newer systems without having to remove and replace old equipment. Fortunately this can be done. Service teams can upgrade their own systems, and those systems manufactured by other companies. This can be done on current and discontinued systems. Conversion can occur slowly, and in stages; therefore, if a pump is off line for maintenance, it might be the perfect opportunity to replace the MCC bucket with a newer model. Like its automation counterparts, this migration method oftentimes can be accomplished slowly and
Figure 3
Illustration of how power is used and paid for.
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