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Service Panels : Ashland Community Plant, Easton, PA

Infrared Electrical Survey
Ashland Chemical
Investigation: 3/26/96

Table of Contents

  1. Abstract

  2. Electric Scan

  3. Profile

  4. Infrared Analysis Summary

  5. Thermographic Analysis

  6. Illustrations

  7. Electrical Survey Recommendations
    Corrective Action

ABSTRACT

An infrared survey is conducted for the purpose of locating circuits with higher temperatures. Panel boxes, elevator switches, and power lines Are all examined as instructed by building personnel. Possible problems that may cause increased surface temperatures of circuits include faulty manufacturing breaker, loose connection, loose wire on breaker, or overloaded circuits.

In circuit panel boxes, slight temperature increases of about 2°F to 6°F may indicate a possible deficiency, but not one of immediate concern. These temperature increases may also be normal operational temperatures for the loads being used through indicated circuits. Only through subsequent surveys can these anomaly areas be confirmed problem areas. Temperature gradients exceeding this value and particularly those in excess of 10°F are considered to be moderate to serious deficiencies, and should be attended to as soon as possible.

On elevator selector switches temperatures increases are of a much higher range. This is due to the mechanics and loads of these switches. Anomalies of the elevator switches can appear over 100 degrees higher than ambient.

Departures from normal gradients expected in switch gears and circuits is an indicator of a defect in materials or connections on current carrying positions. Abnormalities such as these are due to installation techniques or long term expected deterioration. Suspect faults can eventually result in general degradation of switchboard components.

It should be noted that the infrared analysis records instantaneous data on energized suspect areas, therefore the “rate” of deterioration cannot be determined. A yearly maintenance program including an infrared study would substantially reduce the risk of low voltage burndowns.

Each switch and circuit box is labeled, and the departure from normal temperatures are indicated in the Thermographic Analysis of this report. The circuit breaker boxes surveyed that contained circuits with temperature gradients of 15 degrees F and higher may require immediate attention. The circuits should be checked by qualified electricians to determine if the circuits can take the load (amps) being used.

The elevator selector and contactor switches showed departures from ambient temperatures of a much higher degree. The infrared thermographers are not trained in elevator control equipment, therefore, qualified elevator electricians are needed to determine if the temperature increases are normal for this type of switch. Increases from ambient are seen in most of the car contactors, however, some contactors show an increase of over hundred degrees.

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PROFILE

ELECTRIC PANELS SCANNED:
Building #7
M.C.C. panels and circuit breakers
Building #19A
circuit breakers and panels

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ELECTRIC SCAN

Conducted on the survey date was an electrical systems analysis utilizing the infrared camera to detect hot circuit breakers and switches. Connections of electric service panels generate heat when the circuit is in operation. If there is a malfunction in the circuit, the level of heat generated will become elevated. It is this elevated temperature above normal operating or ambient temperatures that the infrared camera detects and records.

The thermal information is recorded on videotape, and later processed into black and White Thermograms only, depicting hot spots as white. Each circuit box and/or control switches were analyzed for ambient surface temperature, then the temperatures were taken of each hot spot using the in-camera temperature measuring devices. The actual temperatures are indicated in the Thermographic Analysis Section of this report. Each circuit and main panel were examined, however, only those with increased temperatures were recorded for further analysis. Panels without elevated heat are assumed to be functioning normal (at the time of the survey), or were not in operation.

Included in the Electrical Survey Section of this report are the following:
Evaluation- Offers information as to the possible causes of problems seen during the survey.
The Infrared Analysis Index- Outlines the findings of the survey.
Thermographic Analysis- Details the findings of the survey, including temperature gradients, illustrated through infrared thermograms.

It is suggested to conduct a second infrared analysis of all circuit boxes and switches six months after the initial survey, in order to obtain thermal data for comparison. Changes in electrical load due to differences in exterior temperatures as well as additional electrical usage, may give different thermal readings, which would be useful in a comparison study.

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INFRARED ANALYSIS SUMMARY

This section of the report summarizes the findings of the electric survey, and references the results with the photographs in the next section.

Location

Panel

Circuit/Fuse

Temp. Increase

Photo #

Bldg. #7

KoHpump

all

0.0

1

Bldg. #7

CV1O6 Bot. Conv.

all

0.0

2

Bldg. #7

P207-HF Pump

all

0.0

3

Bldg. #7

PP3

#2

15.3

4

Bldg. #7

PP2

all

0.0

n/a

Bldg. #7

2OHP Scrubber fan wires

 

9.3

5

Bldg. #19A

Boiler Room

3 connectors

22.3

6

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THERMOGRAPHIC ANALYSIS

The sets of thermograms depict thermal anomalies seen during the electrical survey. The information supplied on each page is as follows:

1. Building Section
2. Photo Set Number
3. Panel Designation
4. Circuit Number
5. Ambient Temperature
6. Anomaly Temperature
7. Temperature Increase from Ambient
8. Priority Scale

For Panel Designation, refer to the information listed on the Illustrations Page, the Infrared Analysis Summary (for location), and to the Visible Light Photograph (for exact panel designation).

Circuit Numbers and/or fuses listed in this section were confirmed with the infrared camera imagery and identified visually (as marked on the panel boxes).

Priority Scale can be interpreted as the following: All identified anomalies require attention in some form or another. The greater the temperature increase, the greater the importance of identifying the cause. Temperature increases seen at 10 degrees F. or less are not listed, as they can be assumed to be normal working temperatures. Increases that are seen as 10 degrees F. to 19 degrees F. are marked as Priority 3 on the thermogram pages. These circuits may or may not have a problem, as the temperature increases may be normal for those circuits. It is suggested, however to evaluate the circuits for potential problems as time and materials permit. Parts are usually repairable.

Temperature increases of 20 degrees to 49 degrees F. are marked as Priority 2, indicating a greater possibility of circuitry problems. Try to correct the problems soon. Parts are still usually repairable, but may become permanently damaged soon.

Circuits listed with temperature increases of 50 degrees F. and higher, are marked as Priority 1 and should take top priority in electrical service. Parts will often require replacement due to thermal stress. Attempts to simply tighten connections will probably not offer permanent repair.

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ILLUSTRATIONS

Infrared Thermogram 1

Infrared Thermogram 6

   

Visible Light Photo 1

Visible Light Photo 6

LOCATION

Bldg. #7

Bldg. #7

PANEL

KOH Pump

CV106 Bottle Convertor

CIRCUIT

all

all

TEMP.
INCREASE

0 F

0 F

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ELECTRICAL SURVEY RECOMMENDATIONS

At a minimum, a preventative maintenance program should include the following items:
1. Check and clean wiring connection points.
2. Take an amp reading at each identified circuit or fuse.

Special attention should be made at anomalies with temperatures of 20 ° or more above ambient temperatures. Connections should be tightened and amp readings taken, to be sure the circuit is not overloaded. If an overload is determined, the usage of the circuit should be re-directed.

Thermal anomalies identified at wires may indicate that either the line is being overloaded or the wires are insufficient for the load being used. Check wires at identified anomalies to be sure they are the proper size.

Maintenance repair duties should be conducted by qualified electrical specialists, as working on indicated anomaly areas may be hazardous. For example, the affected circuit should be de-energized due to the high risk to personnel when tightening components in place on live apparatus. This is due to the possibility that insulating materials between conductors or ground have deteriorated or carbonized to a point where torque tightening pressure would cause final breakdown through that insulating medium. The maintenance mechanic would then be in direct contact with a bolted or ground fault condition. Also, connections of hardware or pole pieces may have annealed due to excessive heating causing reduced strength. Torquing pressure might then destroy the connection hardware, again subjecting the mechanic to fault condition hazards.

It should also be noted that burrs of foreign material may prevent the seating and surface conductivity of bolts and washers, etc. Torque tightening may then actually be ineffective although tightening is registered. In view of this possibility and in the interest of true cost effective power continuity, bus bar connections, or circuit breaker pole pieces should be disassembled, cleaned with slow residue solvent and re-silvered.

It is recommended that all deficiencies as described in this report, be addressed through proper maintenance and repair, and be re-scanned subsequent to their repair. This will insure proper corrective measures were taken.

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CORRECTIVE ACTION

To further explain the irregularities that are depicted in infrared inspections, we are providing further information on some of the most common problems.

1. ELEVATED FUSE BODY OR BREAKER HOUSING TEMPERATURES
Fuse body/breaker housing temperatures may be elevated for several different reasons.
The fuse/breaker may be overloaded (in excess of 80% of its rated capacity) due to:
a) additional permanent and temporary loads being added to the circuit,
b) the load may be straining or previously strained due to mechanical reasons (i.e.,. dirt, improper lubrication, modified tooling, previous motor seizure or failure, etc),
c) voltage drops (primarily due to poor connections) prior to or at the fuse.

Fuses/breakers very often display an elevated body temperature due to simple internal degradation. The internal connectors wear and become loose due to normal cycling of the unit. Also when temporary load strains weaken but do not completely fail the fusible link/thermal element, this will effectively lower the fuses/breakers ability to operate at its rated capacity.

All of these circumstances will cause your fusing to fail premature. In cases such as internal degradation and voltage drops it will cause failure without any apparent reason and often at the most inopportune times.

2. ELEVATED CONNECTOR TEMPERATURES

Although elevated connector temperatures are primarily due to loose connections, they may be due to a poor connection as well (i.e.,. conductor strands that are cut or bent away from the connector, dirt accumulations and conductor insulation inside the connection).

If a connector is just simply tightened, even at low temperature rises, dirt may be compressed in the connection creating tiny gaps in the connector that may lead to arcing and pitting. At high temperature rises, when arcing and pitting is present, if the connector is just imply tightened the pits and subsequent carbon accumulations will allow arcing and pitting to continue. This will usually provide only an improvement or temporary repair of the problem.

We recommend that the connection be removed, cleaned and inspected (both lug and conductor or spade) prior to tightening the connection. When a temperature rise above 50 degrees F is noted, ensure that arcing and pitting is not present, but if it is detected, it would be best to replace the affected connector parts.

3. ELEVATED CONDUCTOR TEMPERATURES

Elevated conductor temperatures may be caused by utilizing an undersized conductor or a properly sized conductor that has broken, cut or bent strands at both connections. These situations will cause the conductor to have a very constant elevated temperature over the entire length. Whereas if the conductor had broken or cut strands in the center of its length it would cause the temperature to elevate in that area.

Conductor may also have elevated temperatures when they are over-crowded in conduit or cable trays and also in situations when simply too many are tied together.

4. ELEVATED SPRING CLIP CONNECTOR TEMPERATURE

Spring clip failure is commonly caused by improper removal and installation of the fuse (i.e.,. using screwdrivers, etc.) causing the spring clip to become bent or deformed and not allowing a proper connection to the fuse. These are very difficult to simply bend or tighten due to the tendency for it to deform at a different area when attempting to repair the original problem.

We recommend that the spring clip be replaced and inspect the fuse head for arcing and pitting and replace it as necessary, especially since the fuse is often degraded due to conductive heat or subsequent voltage drops created by the defective spring clip.

5. ELEVATED BEARING HOUSING TEMPERATURES

Bearing failures are commonly caused by overlubrication/overpressurization. The most common cause of overlubrication is the lack of an adequate program and tracking system. If over or under lubrication is indicated and you are uncertain of the lubrication frequency and volume, it would be difficult to determine how to best correct the situation. We have found it to be extremely beneficial to either utilize a form of log or bearing tag to document your program. The critical information to be recorded is:
a) Bearing Identification
b) Standard Lubricant
c) Standard Lubrication Frequency
d) Standard Lubrication Volume
e) Date of Lubrication
f) Amount of Lubricant Added
g) Name of Lubricator

This information will not only allow you and your staff to make adjustments due to missed lubrication frequencies and lack of communication between lubricators, it will allow you to make simple adjustments when either under or over lubrication is determined.

For more information on all of the above Corrective Actions, please contact Abacus Group Ltd.

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