(A) Available voltages and transformer size limits shall be according to the following table and the table in division (B) below.
Voltage | Transformer Size Limits |
Single phase; 120/240 volts | 250 KVA |
(B) Voltages listed below are not available at all locations. TCED must be consulted regarding voltage availability at any particular location. When the customer's load requirements are greater than the maximum listed below, TCED will supply additional or other facilities at the same location, which facilities at TCED's option may be considered excess facilities.
Voltage | Transformer Size Limits |
Three phase; 120/208 | 750 KVA |
Three phase; 120/240 volts (four-wire delta) | 367 KVA1 |
Three phase; 240 volts delta | 750 KVA |
Three phase; 277/480 volts wye | 1,500 KVA |
Three phase; 480 volts delta | 1,500 KVA |
Notes to Table: | |
1 Customer size limit 357 KVA (2-100 KVA and 1-167 KVA transformer) | |
(C) (1) Appliances or devices with a rating of greater than 20 amps shall be connected at 240 volts.
(2) Single phase motors up to but not exceeding ten horsepower may be connected to a single phase lighting service under the following conditions:
(a) Single phase motors not in excess of three-fourths horsepower may be wound for 120 or 240 volts and may be operated from a lighting branch circuit.
(b) Single phase motors, one horsepower to ten horsepower inclusive, must be wound for 240 volts, be connected across the 240-volt legs of a 120/240 volts three-wire service, and be operated from a branch circuit separate from any lighting.
(c) Upon approval by TCED, single phase service will be made available to a phase converter where system conditions permit and where the name plate rating of the largest three phase motor does not exceed 50 horsepower, and where the combined name plate ratings of all three phase motors does not exceed 75 horsepower.
(d) Service to any intermittent or highly fluctuating load must be reviewed and approved by TCED prior to the installation of the equipment. Approval for installation does not relieve the customer of responsibility for conditions that cause a deterioration in the quality of service either on the customer's premises or on another customer's premises which is connected to the same electrical system. TCED reserves the right to disconnect any service or service premises which are impacting quality of service conditions for other customers. This includes the customers whose connected equipment are generating electromagnetic radiation which interferes with any communication equipment of others.
(e) Service to any motor rated greater than ten horsepower must be reviewed and approved by TCED prior to the installation of the equipment. Upon approval, service to any motor rated greater than ten horsepower will be considered a power installation and will be served under TCED's applicable power rates, with the exception of a softstart single phase motor in excess of 10 horsepower, where the starting current of the motor does not exceed the starting current of an equivalent conventional ten horsepower single phase motor and where system conditions permit.
(D) (1) TCED supplies different voltages and types of polyphase service in various locations. In all cases, TCED must be consulted regarding the character of service available at any particular location.
(2) TCED will supply single phase or polyphase service for power in accordance with the following general provisions:
(a) Installations having motor load aggregating ten horsepower or less will ordinarily be supplied with single phase service. The customers requiring polyphase service within this rating should consult TCED regarding the availability of the service for their particular application.
(b) Installations having a motor load aggregating more than ten horsepower may be supplied either single phase or polyphase service, depending upon the particular application and the availability of polyphase service at the customer's premises.
(c) TCED may require the use of any starting or current limiting equipment as may, in its opinion, be necessary for use with any motor or apparatus to prevent undue disturbance, unbalance, or voltage fluctuations on its lines. Electric welders, X-ray devices and similar equipment usually require a separate power supply for satisfactory operation. TCED should be consulted in every case prior to the installation of the equipment.
(d) Electric furnaces and other heating devices shall be energized in a manner that TCED's system will not experience undue disturbances, unbalance or voltage fluctuations.
(E) (1) Voltages listed below are not available at all locations:
(a) Three phase; 2400- volts delta;
(b) Three phase; 2400/4180-volts wye; and
(c) Three phase; 8000/13,800-volts wye.
(2) TCED's Engineering Department must be consulted in each case relative to service availability and transformer size limits.
(F) (1) Customers may be supplied at the following voltages as determined and specified by TCED:
(a) Three phase; 68 KV; and
(b) Three phase; 138 KV.
(2) TCED's Engineering Department must be consulted in each case relative to service available and transformer size limits.
(G) (1) TCED will designate the specifications and location at which overhead service lines will be connected to the customer’s facilities.
(2) Underground service is subject to special conditions and policies making it necessary to consult TCED before wiring or rewiring the premises. When underground service is supplied, the customer must enter into an agreement with TCED designating the point of connection of each underground service to the customer’s facilities. In some cases TCED will require curb side metering.
(3) Any changes made in service connections, either overhead or underground, at the customer’s request after the original installations shall be at the customer’s expense.
(Res. R990419d, passed - - )