Service Ampacity for Apartments #1
What is the minimum ampacity of the feeder conductors for a dwelling unit in an apartment building that is 100m2 and has a total calculated demand of 15 kW?
62.5A
15000/240 = 62.5A
8-202
What is the minimum ampacity of the feeder conductors for a dwelling unit in an apartment building that is 100m2 and has a total calculated demand of 14.3 kW?
60A
14300/240 = 59.58A
60A > 59.58A. Therefore, minimum is 60A due to 8-202 1) b)
Each subdivision of a main consumer's service shall be provided with a separate service box or equivalent multi-service equipment shall be used unless a deviation is allowed by special permission. True or false?
True
6-202
If a service box embodies one or more fuse holders, access to which may be had without opening the door, such fuseholders and their fuses shall be completely enclosed by a separate door, spring-closed, or with a substantial catch. True or false?
True
6-204
What is the minimum size of copper grounding conductor in an apartment complex, when the main service conductors are 250 kcmil, RW90 aluminum?
#6 AWG
10-114
What is the basic load (in watts) of an apartment with a living area of 105m2?
6000W
First 45 - 3500WNext 45 - 1500W
Remainder - 1000W
8-202
A branch circuit is supplying a 15kW range in an apartment unit. What demand is applied to the service feeder calculation?
6000 + 0.4*3000 = 7200W
8-202
Which rule states that if there is more than one service box each box shall be labeled in a conspicuous, legible and permanent manner, to indicate clearly which portion of an installation it controls.
6-214
If the rating of the metering equipment does not exceed _____ A, it may be placed on the supply side of the service box.
200A
6-402
If the rating of the metering equipment does not exceed _____ V, it may be placed on the supply side of the service box.
300V
6-402
An apartment unit has a space heating load of 2.5kW and an AC load of 3.5kW. The space heating and AC can NOT be operated at the same time. What is the load on the apartment panel?
3.5kW
What is the demand on the apartment feeder for an electric appliance with a rating of 1300W if an electric range has been provided for?
0kW
What is the purpose of a current transformer as it pertains to service metering?
Steps down the current to small values in a ratio to the actual line current
What 2 types of transformers are considered part of "metering equipment"?
Current and voltage
6-400
In what method of metering (line side or load side) is multiple-lug metering equipment used?
Supply side or line side
A panelboard supplies 83 controlled automobile heater receptacles, each with a 15A rating. What is the total calculated demand load for the feeder conductors supplying the panelboard?
46350W
30 x 650 = 19500
30 x 550 = 16500
23 x 450 = 10350
19500 + 16500 + 10350 = 46350W
8-400
The total space heating load located within the dwelling units in an apartment complex is 60kW. What is the total space heating demand to be added to the main service conductor calculation?
47.5kW
First 10kW @ 100% = 10kW
Next 50kW @ 75% = 37.5kW
62-118 3)
What is the maximum number of consumer's services that can be terminated to one supply service at a building?
4
6-104
When a sub-panel is installed on the load side of a service box, what must be removed from the sub-panel?
The bonding strap or screw
10-210, 10-624
Which table is used to determine the AWG size of equipment bonding conductors?
Table 16
What is the minimum size of rigid metal conduit required for two 300 kcmil and one 250 kcmil RW90XLPE 600V unjacketed conductors?
#53
Table 6A: 2 @ 300kcmil = 585.11
1 @ 250kcmil = 251.65
Total = 836.76
Table 9G -> #53
A service supplies two apartment dwelling units.
The calculated demand load for unit 1 is 14.5 kW and 13 kW for unit 2. The supply is 120/240 V single-phase.
What is the minimum main service conductor ampacity?
95.625A
100% x 14.5kW = 14.5kW
65% x 13kW = 8.45kW
Total = 22.95kW -> 22.95kW / 240V = 95.625A
8-202
Who determines the space requirements for meters and what rule states this?
The supply authority
6-410
Is it permissible for enclosures for circuit breakers and externally operated switches to be used as junction boxes, troughs or raceways for conductors feeding through or tapping off to other electrical equipment? Answer yes or no AND the rule that tells us this.
No
6-212
Overhead service conductors are required to have _____ loops. What rule states this?
Drip
6-302 3)