Michigan Switchgear Services, Inc

Power Quality Survey

Michigan Switchgear Services Power Quality Testing takes a three-tiered approach to resolving your power quality issues.

Each level builds on the previous; assuring that your problems can be identified in the shortest amount of time and at the least expense.

The Level 1 Survey

Since most power quality problems stem from building wiring and grounding problems, the Level 1 Survey emphasizes testing and analysis of the AC distribution and grounding system.

The Level 1 Survey is comprehensive-starting outside at the building electrical supply and grounding points, working though the internal wiring and grounding distribution system, and finally to the electrical receptacles or connection points supplying the user equipment.

If a qualified person is available to make corrections, Power Quality Testing immediately retests the device or equipment to ensure that the repairs were made correctly.

Short term, day of Survey, electrical waveform analysis is performed at locations chosen by the customer. While this is too short a monitoring period to produce a general statement about the facilities overall quality of AC waveforms, it does provide the customer a detailed snapshot of what happened during that particular day. An added benefit of the Level 1 Survey is that it can be used to supplement OSHA (or State) safety and health programs by documenting electrical hazards.

The Level 2 Survey

In some cases, long term monitoring of the building power is required to detect harmful voltage and current anomalies that may

occur. This is the focus of a Level 2 Survey.

 

Unlike the recorders that are used by many electricians and Utility companies that simply record the voltage and/or current once

every second (once every 60 cycles), Power Quality Testing uses state of the art analyzers that allow us to capture only the events

that exceed predetermined threshold levels. The advantage to you is two-fold:

First, we can capture events that are sub-cycle in nature such as transient over voltages. Sampling the voltage or current once every second is ideal for energy consumption or load analysis surveys, but it simply allows too many waveform distortions to pass by undetected.

Second, it makes for a more useful final report to you by eliminating useless pages of printouts. Recording voltage and current readings on a three-phase system once every second generates over half a million data points every day, almost all of which are worthless for an effective power quality survey. Another drawback to these types of recorders is that they can produce dramatically different results.

The Level 3 Survey

The Level 3 Survey is normally required only in special cases. This Level of Survey focuses on measuring environmental factors such

as temperature, humidity, and electro-magnetic interference.

Power Quality Testing has chosen to include thermal (infrared) imaging under the Level 3 Survey for one simple reason: any electrical problem detected by thermal imaging must be confirmed using procedures in a Level 1 or Level 2 Survey. All too often this technology has been misapplied or the readings misinterpreted by inexperienced camera operators. Be wary of any consultant (or electrical firm) that uses a thermal imager as the primary tool when conducting a power quality survey. These imagers should supplement a survey, not drive it.