36C24218Q0077-00003001.xls

VISN 2 MASTER

&L&"Monotype Corsiva,Regular"&8Page &P of &N&C&"Monotype Corsiva,Regular"&8Department of Veterans Affairs&R&"Monotype Corsiva,Regular"&8&F

Albany

&L&"Monotype Corsiva,Regular"&8Page &P of &N&C&"Monotype Corsiva,Regular"&8Department of Veterans Affairs&R&"Monotype Corsiva,Regular"&8&F

CODE REQUIREMENTS

(1)Checking of connections (2)Inspection or testing for evidence of overheating and excessive contact erosion (3)Removal of dust and dirt (4)Replacement of contacts when required A.8.3.5 Where sealed devices are used, replacement of the complete device might be necessary. Maintenance should be performed according to manufacturer’s recommendations. In the absence of such recommendations, the list given in 8.3.5 suggests minimal procedures.

Transfer switches should be subjected to an annual maintenance program including (one) major maintenance and (three) quarterly inspections. Programs should include all of the following operations. Note: Due to the critical nature of these devices, permission should be gained to perform these tasks since some of the following recommendations could cause disruption of power to the load. The following tasks should be carefully reviewed with facility management personnel to ensure agreement and plan for contingencies.

Major Maintenance

(1)Check connections.

(a)A thermographic or temperature scan should be done prior to this visit, while the ATS is under normal (peak) load. This thermographic scan should be repeated during the EPSS load test. Results should be available to the maintenance provider so that suspect conditions can be addressed during this activity.

(b)With power connected to the normal source, measure and record millivolt drop levels across each pole. Note: Any reading that is greater than 25 percent of the average of all poles should be carefully inspected when the ATS is de-energized.

(c)With power connected to the emergency source, measure and record millivolt drop levels across each pole. Note: Any reading that is greater than 25 percent of the average of all poles should be carefully inspected when the ATS is de-energized.

(d) If the ATS is equipped with a bypass isolation feature, operate the bypass to the connected source (emergency or normal) and repeat the steps in (a), (b), and (c). Levels should drop to approximately 50 percent of initial levels and be uniform relative to initial readings. This step verifies that the bypass feature is properly connected and that the connected load will not be affected when the automatic portion is isolated for maintenance.

(e) With power secured and both the emergency and normal sources properly locked out and tagged out, measure the micro-ohm resistance levels across the following connection points:

i.Emergency source cabling lug to bus ii.Normal source cabling lug to bus iii.Load cabling lug to bus iv.Neutral cabling lug to bus v.Load connected to normal across each pole vi.Load connected to emergency across each pole

Note: If the ATS is equipped with an isolation bypass and the bypass remains energized, perform these tests on the isolated transfer switch unit only. DO NOT APPLY DIGITAL LOW RESISTANCE OHMMETER (DLRO) TO ENERGIZED CIRCUITS. Any value greater than 20 percent of the average value of all similar type connections requires further investigation.

(2) Inspect or test for evidence of overheating or excessive contact corrosion.

(a) With power from both sources secured and properly locked out and tagged out, remove all protective pole covers and arc chutes.

(b) Carefully inspect main contacts and other current-carrying parts for signs of corrosion or overheating. Note: Observation should correlate with previous results (i.e., thermographic or temperature evidence of higher than normal temperatures or heat migration, abnormal millivolt drop readings as previously noted, or abnormal micro-ohm (DLRO) readings as previously noted).

(c) Carefully inspect insulating materials or standoff insulators for signs of contamination (dirt, grime, oil, etc.). The combination of contaminants and possible introduction of high humidity or moisture could lead to insulation breakdown and subsequent destructive faults. Clean contaminated surfaces with a solvent approved for this purpose.

(d) Inspect control connection, plugs, and harnesses for signs of corrosion, heat, contamination, and so forth.

(e) Using a vacuum, remove all dust and debris from the ATS cabinet, transfer switch mechanism, bus, and so forth. Note: Never use compressed air to blow out dust. Doing so can blow dust and debris into controls and the transfer switch mechanism.

(f) Inspect cabinets for proper sealing. Open conduit knockouts or other penetrations should be properly sealed to prevent the introduction of dust, moisture, or other alien matter. Enclosures installed outside should be inspected for proper seal and appropriate gasketing. Ensure that enclosure door securing devices are intact and properly secured.

(g) Replace and secure all protective pole covers and chutes. Remove lockout devices and resupply normal power. If the ATS is of the bypass isolation type, reconnect the transfer switch mechanism. Observe proper manufacturer’s procedures.

(3) Verify control and feature setpoints and operation.

(a) Measure and record the following data and setpoints:

i. Normal source voltage phase to phase, phase to ground, and phase to neutral

ii. Engine start time (from crank start to source available light or relay pickup)

iii. Emergency source voltage phase to phase, phase to ground, and phase to neutral

iv. Load current each phase

v. Momentary override normal deviation where provided

vi. Transfer time delay where provided

vii. Return to normal source time delay where provided

viii. Engine cooldown where provided

(b) If the connection is to a multiple-source EPS, verify the load priority of the ATS being tested and confirm this is correct given the criticality of the connected load.

(c) Verify proper operation of all indicator lights and meters and controls.

(d) Return ATS to normal service Quarterly Inspections

(1) Visually inspect the transfer switch control mechanism, control panel, harnesses, and cable connections for signs of moisture, corrosion, or heating.

(2) Measure and record the following data and setpoints:

(a) Normal source voltage phase to phase, phase to ground, and phase to neutral

(b) Engine start time (from crank start to source available light or relay pickup)

(c) Emergency source voltage phase to phase, phase to ground, and phase to neutral

(d )Load current each phase

(e) Momentary override normal deviation where provided

(f) Transfer time delay where provided

(g) Return to normal source time delay where provided

(h) Engine cooldown where provided

(3) If the connection is to a multiple-source EPS, verify the load priority of the ATS being tested and confirm this is correct given the criticality of the connected load.

(4) Verify proper operation of all indicator lights and meters and controls.

(5) Inspect cabinets for proper sealing. Open conduit knockouts or other penetrations should be properly sealed to prevent the introduction of dust, moisture, or other alien matter. Enclosures installed outside should be inspected for proper seal and appropriate gasketing. Ensure that enclosure door securing devices are intact and properly secured.

(6) Perform a load test using the test switch if permitted. Note: This will cause the emergency power source to start and the ATS to transfer. Be sure to gain permission from the facility management prior to performing this test.