final bid specs 09328.pdf - Freese and Nichols, Inc.

5. A relay coordination study shall be performed to determine appropriate relay settings. The
study shall include all electrical equipment provided under this contract and any up-stream
equipment that has an impact on the coordination study. The study shall show transformer
damage curves, generator damage curves, cable short circuit withstand curves and motor
curves. Include all medium and low voltage switchgear, distribution switchboards, motor
control centers, starters, and panelboards main circuit breakers. Complete the short circuit
study down to the main breaker or main lugs on all panelboards. Panelboard branch circuit
devices need not be considered. The phase over current and ground-fault protection shall be
included as well as settings for all other adjustable protective devices. All motor monitoring
relays and protective or monitoring devices that are a part of a supplier’s equipment (such as
soft starters, switchgear) shall be in included. Include the last protective device in the Electric
Utility’s system feeding each facility being considered.
6. Provide Time-Current Curves on 11X17 log-log paper. Do not put more than one branch of
protective devices on any one coordination curve. Include a one-line diagram and the names
of each protective device in the branch. Use the names designated in the Contract
Documents. Include motor and transformer damage curves, and cable short circuit
withstand curves. Coordination study time-current curves (11x17 log-log type) including the
instrument transformer ratios, model numbers of the protective relays, and the relay settings
associated with each breaker. Organize the curves as specified here in. Ground fault time
current curves shall be on a separate sheet.
7. An equipment evaluation study shall be performed to determine the adequacy of the fault
bracing of all bus from the panelboard level up to the main Panelboard or protective device.
Include circuit breakers, controllers, surge arresters, busway, switches, and fuses by
tabulating and comparing the short circuit ratings of these devices with the available fault
currents.
8. Provide arc flash hazard analysis in accordance with the applicable NFPA, ANSI, and IEEE
standards.
9. The studies shall be performed, sealed and signed by a Registered Professional Engineer
licensed in the state of Texas.
10. Any problem areas or inadequacies in the equipment shall be promptly brought to the
ENGINEER's attention.
11. Use industry standard short circuit software, SKM CAPTOR and DAPPER or an equal
approved by the ENGINEER.
12. The report shall include a comparison of short circuit duties of each bus to the interrupting
capacity of the equipment that is protecting that bus.
13. The report shall include all data that was used as input to the report. This data shall include
cable impedance, conduit type, source impedance, equipment ratings, motor X/R and
subtransient reactance data, etc.
14. The CONTRACTOR shall coordinate with the OWNER for electrical data required for the
studies.
1.02 REFERENCES
A. This Section contains references to the following documents. They are a part of this Section as
specified and modified. In case of conflict between the requirements of this Section and those of
the listed documents, the requirements of this Section shall prevail.
Reference
IEEE 141
Title
Recommended Practice for Electric Power Distribution for Industrial
Plants
IEEE 242
NFPA 70E
Recommended Practice for Protection and Coordination of Industrial and
Commercial Power Systems
Handbook for Electrical Safety in the Workplace
Electrical Power System Studies 26 05 73.01-2
DRP09328