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What are some other names for a "loop"?
During storm work, if a breaker box isn't usable due to damage, what should you do.
Don't connect the service. We must have a disconnect between the customer and us for safety reasons.
What transformer size is typical for OH services?
Varies depending on customer load. Could be 25kva, 50kva, etc
On a 3phase OH Delta system, must transformers be the same size?
No. Depending on how large the customer's 120v usage is, the "lighter can" may be larger than the other 2 cans, but not necessarily.
On 3phase Wye systems, do all transformers have to be the same size?
Yes, to maintain balanced loads.
If you see a transformer bank with 2 or 4 bushing cans, what size service would you expect to see?
What are the physical differences between the following?
- Switch Cabinet
- Primary Metering Cabinet
What size transformer is a typical residential padmount?
Generally 25,50 or 75KVA depending on the anticipated load.
When do you enter I910 instead of W60 on the completion form?
On "bi-directional meters" only.
Why must you disconnect the meter before cutting the lateral?
For safety. Backfeed through the meter's potential coil may cause an arc.
How does Rudy want slip sleeves installed?
- -Cut Riser 1st(while still attached to wall for stability)
- -Remove meter housing completely
- -Attach slip sleeve and attach meter housing before mounting to house.
Why can't conductor size exceed 750Kcmil?
Because the line dept doesn't have larger connectors.
How many Xfrm banks allowed per customer?
- One. (pg 18 #3)
- Except for special conditions(pg25)
- -emergency lighting
- -fire pumps
- -standby systems
- -parallel power production systems
Can meter sockets be installed on company poles?
What size & material must risers be?
Per NEC, 2"GRC or Sched 80 PVC. But it is the inspectors responsibility to determine. Not ours.
What is required if a service is disconnected or shutoff for over a year?
- Service must meet current requirements and have an inspection release.
- (section 2 pg 21)
Do RTD or railroad installations need an inspection?
- No local public authority.
- (section 2, pg21)
Where do we find what services are available in Colorado?
In the Tarrifs.
Does Xcel provide 2 wire services?
Where is this stated?
How many services are allowed per building?
- Except for special conditions(pg25)-emergency lighting-fire pumps-standby systems-parallel power production systems
Is a firepump meter required to be located near the other meter?
Are Firepump meters hot or cold sequenced?
No. Can be located anywhere.
- Must be hot sequenced, so CT's may be used even though below 400amps. (Per Denver)
- ---MUST BE IN WRITING---
Is there an exception for hot sequencing a 3phase meter?
- No exception, but keep in mind that a residential 3 phase well should be hot sequenced as it is residential.
- Cts may be used even under 400 amps when required (firepumps etc)
Is it ok to have Firepumps wired directly to the Load Side of the CTs?
Why must we have a neutral to the Line side of the cts?
For metering purposes.
Define Catinary Loop:
- Some say it's a triplex loop coming off an open secondary.
- Others say its when the secondary makes a midspan 90degree turn.
Are customer fuses allowed in Vaults?
- No. No customer equipment of any kind.
- (section 4 pg 32)
Name the 3 types of primary.
How many House Meters are allowed per building?
How is it determined that a commercial customer needs SG rate.
If over 3000kwhr/month, we monitor to see if they go over 25KW.
What billing rate is used for a FM16?
Either Commercial or Secondary General, depending on whether over 25KW.
What roof pitch is considered "Flat Roof" per NEC?
Anything under 4/12
What is the minimum voltage required to light up a meter?
Can full-voltage be determined if ABC light up on a 3 phase meter?
- If one leg is dead, meter can pick up voltage via the customer load. Occurs when 1 fuse is blown, for example.
If the disk is moving on a FM2 electromechanical meter, do you have full voltage?
- No. The disk may still turn if one leg is dead.
- The pot coil is energized at 120v or less depending on load. If the load is on, on the dead side, the pot coil will be energized via the customer load, thus turning the disk.
- If a load is on, only on the live side, the disk will not turn.
Where does it say a service must be upgraded if new load wires are installed?
Where does it say I have to Upgrade my service?
2nd paragraph of Foreward.
Where does it say a customer can't cut a seal?
Section 2, page 16
Where does it say the EMD must enforce the BB?
In the Introduction of BB, plus the tarrif includes the BB (see Forward), so we must enforce.
Where does it say exceptions must be requested in advance?
Where is the word "SHALL" defined?
Where does it say the customer will provide keyless entry 24/7?
Section 4, pg 48
What exceptions can we grant?
Any that pertain to "local meter personnel".
Why can an electrician cut a loop and "temp" in a service when section 2 (Connection) says they can't?
Because there is an exception.
Do we get bonuses on authorized closed loops?
If over 30 days we do.
Where does it say no customer attachments or surge protectors allowed?
Where does it say failure to comply may result in disconnect of service?
How can the "lighter can" be identified?
By the center tap, or larger can.
Why don't Delta banks need to be balanced?
Because of the wild leg.
How many meters are allowed per Building/Unit?
- Each meter must have it's own address.
- Each unit(like a strip mall) must be enclosed by 4 walls (imaginary or real).
- No intermingling of wires between units (this splitting of load is often tried to keep demand low)
What is considered voltage unbalance on a 120v system?
Per BB, +/- 3% (pg 65 of BB)
What is nominal voltage on a 120v system?
Per PUC +/- 5% which is 116 to 124 volts
Why do you need to lift the Neutral when checking for an open neutral?
To isolate the house ground.
Who do you call to verify "point of delivery" on items owned by PSCU?
Kathy Petree of Service Investigations.
Where is the language regarding Line & Load wires must not be in the same compartment?
Section 4, also Pg 28 #7
Where does it say load side must terminate at a disconnect, not a load?
Section 2, pg 21
Where does it say we must trace the meter?
Section 2, pg 21
What is the metering point?
The meter or CTs. PERIOD!
What is the minimum size and material type for a service mast?
UG line & load conductors shall enter & exit the same side of the socket.
True or False?
What is the maximum number of service risers per building?
6 max, with a single set of conductors in each riser.
Can load conductors exit through either end of horizontals, back or verticals?
No, NOT the left!
Can customer owned conduit be attached to our pole?
No. Not more than 6" above final grade.
How many feet of customer owned conductor must be coiled at the base of pole?
How many secondary runs per phase on a 3 phase padmount transformer?
- 8 runs per phase (24 total)
- 750mil aluminum or 500mil copper
How many days may closed loops be authorized?
7 calendar days. (or temp meter must be installed)
If we own/maintain the lateral, how many residential units can be grouped at one location?
If house meter used, or more than 6 units, the customer owns/maintains lateral.
What is the max amperage for self contained meters?
400amps then CTs must be used.
What is the max breaker size that can be used for a 200amp meter?
What is the max breaker size for a 320amp meter?
In what situation can we install a k-base meter?
No longer allowed per BB.
What metering rates does Xcel use
- SG-Secondary General
- RD-Residential demand
- PG- Primary General
Are closed loops allowed on new services?
Where must the high-leg be located in the meter housing?
In breaker panel?
- In meter housing on the right.
- In breaker panel in the center.
What is the required size and material of slip sleeves?
Who provides and installs them?
18" in length (9" above & below ground)
- 2 1/2" sched 40PVC or
- 3" sched 80PVC
How many services will be supplied to a building or other structure?
Only one. Per NEC
Are jumpers allowed on new services?
No. Only rewires.
What is the minimum depth of UG service laterals?
Per Blue Book, can the center knockout (bottom) of the meter housing be used?
UG temp ground rods will be installed by the customer, not less than 5' from the pedestal. True or False
What is the Max length of 4/0 conductor from the company pole to a temp?
What is the vertical angle of the drop?
- 70' max
- Must be greater than a 45 degree angle.
What is the minimum distance a OH temp can be from a company pole?
UG temp supports shall be where in regards to the utility easement?
Inside? or Outside?
How far must UG temp supports be from a pedestal?
- Pole type - 6' min
- Brace type- 5' min
What are the BB requirements for self-contained meter housings?
- -Steel sockets (no aluminum except on multiple metering)
- -5th terminal in 9:00 position connected with 16AWG wire min.
- -7th terminal connected w/16AWG min
- -Ringless cover, no screws
- -Locking jaw bypass on the right side.
- -Must accomodate a meter seal and padlock.
What are the ID requirements on the following installations?
- -ID must be a brass, steel or aluminum tag attached to the non-removable portion of the meter socket
- -Unit number must also be permanently marked on the breaker, and entrance to the premise
What additional BB requirement does a 320amp meter socket have?
Anti-inversion clip on top right terminal.
When are horn-type sockets allowed?
- On UG 200amp temp housings
- On OH 100 or 200amp temp housings
What are 4 Metering Pedestal requirements?
- -Furnished, installed and maintained by customer.
- -Separate covers on disconnect switch, wiring area, and metering area
- -If enclosed, must have a 8"x8" lexan viewing area
- -Door hinged on right or left. (can be top-hinged with prior approval if it can be propped open with a locking mechanism)
Which of the following structures can meters be attached to?
Mobile homes, construction trailers, fences, manufactured homes.
Only to manufacured homes if on a permanent foundation.
Meters must be located adjacent to and within line of site of the mobile structure it serves (mobile homes, construction trailers, etc)
True or False
What considerations must be taken into account for determining meter locations?
- -May not interfere with sidewalks, driveways or passageways
- -Can't obstruct doors or windows
- -Can be hazardous or impracticle
What are the mounting heights for the following?
Indoor multiple meters-
Outdoor multiple meters-
- Single meters- 4'min-6'max
- Indoor multiple meters- 2'min-6.5'max
- Outdoor multiple meters-3'min-6.5'max
What are the clearances in front of meters?
- 3', 3.5', or 4' deep per NEC
- and 2.5' wide
When are the following allowed?
-Line & load conductors in the same raceway?
- Junction boxes - with approval
- LBs - with approval
- Line & load conductors in the same raceway - never
What is the min distance a temp support brace can be from the point of attachment?
Service equipment on temps must be supplied by the company.
True or False?
False. Customer supplies.
Temp support stakes must be what depth?
What size must temp meter sockets be?
What length conductor must be available for termination in an UG ped for a post type temp? (TM20)
What is the min conductor size in a temp?
Do temps need to be cold sequenced?
Why or why not?
As a commercial unit, no need to be if it is one single phase meter, one loop, where the Fault Current is below 10,000 amps
What is the size and length of liquitite required for temps?
- Min 1", max 1-1/2" diameter
- 12' long
For OH temps, what is the required height from ground to point of delivery?
What size must temp braces be? (TM30)
- 2"x4" min
- extending 3' min from the base
Where must the 5th terminal tickler be connected?
Tied to N in meter housing. (Not to ground, as the ground may inadvertently get cut)
Connect 5th terminal 1st, then tie to N to reduce chance of short by having grounded wire flailing around in housing.
What is the most important thing to remember when installing an antenna to a Smart Sync Meter?
Attach the antenna to the de-energized meter prior to installing the meter. (To protect the equipment)
How long is a temporary service alllowed?
As short a time as possible.
Describe a Catenary Loop.
A loop which makes a sharp turn by using a guide wire to hold it at the turn. Used for easement compliance.
In regards to primary metering, what do we always need to verify.
- - That it isn't being double metered--at cts, then another meter after. (If there are 2 meters, it may be ok, if the 2nd meter is fed from another source)
- - Verify its wired correctly
- - Make sure the CTs are un-shorted.
If you see an OH transformer bank with 2 bushing or 4 bushing cans, what voltage would you expect to see?
How does Rudy like OH connections to be made?
- -Cut wires the same length.
- -Swoop all wires on the same side of mast.
- -Score the bottom and strip down to the score on multiple connections.
Why must you ground the tickler "inside" the meter housing on a FM12?
So the customer can't cut the ground which would cause loss of registration on EM meters and loss of display on Solid State.
Where does it say that once a property is primary metered, we can't have a secondary metering on the same property?
In the Tarriffs.
Does Xcel still allow Flat Rates?
What is the most important thing to remember when installing meter antennas?
Always connect the antenna to the meter prior to installing the meter to prevent equipment damage.
Per Chuck, if a customer replaces parts "like per like", do they need to conform to current BB standards?
- No. Like per like is not altered.
- Upgrading is altered.
What is C&I Billing and who handles?
Commercial and Industrial Billing. All the big stuff. All RUGS
Can masts bend?
What material must they be?
- Yes, they bend.
- Must be GRC. Can be PVC to roofline then GRC above the roof.
What material must risers be?
Any material approved by NEC.
Who enforces the NEC and NESC?
What are they?
Which supercedes the other?
- The electrical inspector
- Nation Electric Code, National Electric Safety Code
- NESC supercedes NEC
What 4 things should you ask yourself as you approach every job?
- Is it:
- SC or TR
- OH or UG
- 1phase or 3phase
- residential or commercial
- ---because different rules apply---
On a 3W 3phase system, if you wiggie from the "grounded leg" to a house ground, what voltage would you get?
Where does it say that on stacked housing, no disconnect is required if 6 meters or less?
National Electric Code
- If all 6 meters are residential, we own, install, maintain lateral.
- If has a house meter or 7 meters, they do.
If a meter says it's a 120v meter, what does that mean?
That the potential coil can handle "up to" 120volts.
What's the difference between 120v/240v/480v meters?
Price. Due to increased wire/insulation size.
What is Cordova's analogy for Demand vs Kwh?
- Demand is like the speedometer (how fast you are using electricity)
- Kwh is like the odometer (total electric usage)
Describe a whathour in laymans terms.
If you ran a single 100watt light bulb for 10 hours, you would use 1Kwh
What is the difference between a ground and a neutral?
- Ground is connected to Earth.
- Neutral returns to the source (transformer)
What is Cordova's analogy for the difference between A,B & C phases?
Timing. It's like a Merry-Go-Round. Each phase pushes current at a different time which allows more efficiency and less effort.
Energy diversion is accomplished 2 ways. What are they?
- Tap ahead of the meter
- or tamper with the meter
What are the 3 things we care about on the load side of the meter? (Cordova-ism)
- 1- Load wires terminate at a disconnect, not a load (dry-pack transformer considered load)
- 2- No line and load wires in the same compartment (gutter)
- 3- Each meter traced.
If you see a copper colored screw in an A-base meter, what could it indicate?
Burning or loose connection
If a building has Self-contained and TR meters, can the CTs be cold sequenced if a main disconnect is used for multiple units?
Terms to know:
Banjo vs crossarm w/triplex, crib or platform, spun secondary vs plex, midspan tap, pole connect, crossarm connect, spaced primary, horizontal or vertical primary, range cable, transmission, distribution, secondary, duplex, triplex, quadraplex, OH housing, bee box, coffin, LI housing, 100amp medium duty lever bypass housing, open quad, open 2 wire, open 3 wire, survey vs billing meter, floating neutral, through leg, earth ground vs cold water pipe ground, flag fuses, wall-pack
What is the "Point of termination"?
- The termination bay of the CT cabinet,
- The cold sequence disconnect, or
- The meter
What is a "survey meter"?
A RUG installed to record the average use of a neighborhood or area.
On commercial single phase services, should you install a demand or non-demand meter?
Determined by the billing rate in the order (C vs SG). If you think the anticipated load will need a demand later, set a demand (pot house for example). Otherwise set non-demand. Saves time on initial programming and when the read dates change, we have to reprogram all demands.
When do we require a customer to be put on a demand rate?
When they exceed 3,000kwh in a month, we install a demand meter, but will not force them to a demand rate unless they exceed 25KW in any given month. Must then stay on demand rate for 1 year min.
What size neutral is required in a housing?
(per Cordova) What ever size the lug will accomodate.
On a 3W3phase with a floating neutral, if the customer taps into the neutral, what would the meter see.
From N to the 5th terminal, meter would see nothing (free power). From N to either other leg, the customer would be over charged as the potential is energized at 240(delta) or 208(wye) instead of 120v(what customer is using) times the load.
How many amps per phase on a CL200 meter?
Why did Xcel use open deltas?
Cheaper, but less ampacity.
On which side of the transformer must a connection cabinet be? What orientation?
Right side (secondary side), within 2 feet, 90 degree or inline orientation.
Where does it say what size disconnect for what size meter?
BB section 4 pg 37 (self-contained)
How are breakers sized?
(per Cordova) To protect the wire.
Will a FM12 EM meter correctly meter if the tickler isn't connected:
-On a delta?
-On a wye?
Yes on delta because the windings in a delta system are in series and are all 120v to N.
No on a wye because the windings are in parallel and the reference to neutral is gone so it will see 104v, not 120v.
If the tickler is cut on a solid state, no display.
Will a FM1 set on neutral meter correctly?
Yes, unless there is an accidental ground.
Why do we always disonnect the N last?
For safety. To keep a neutral bond as long as possible because the neutral can become a conductor via the customer load.
If an electrician provides power to a house from a temp, where is he suppose to make his connections? Why?
To the load side lugs only. Not to the breakers as we don't want to be liable for damage when removing the temp. Not to the line side lugs (with Jumpers) due to backfeed back to the pedestal (hot laterals sitting in pedestal, but not connected in pedestal) Hazard!
What is the rule of thumb for cold sequencing temps?
- Generally cold-sequence out of transformers.
- All xmas tree style temps out of a transformer-cold sequence. (liquitite 12'max)
- Post style temps may not have to be, depending on length of wire from transformer.
Name the 2 types of connection cabinets.
- One with metering provisions (CTs)
- One without.
- We are responsible for lateral to the cabinet and the line side lugs.
Define Fault Current.
The current that flows directly at the fault. Based on wire size and length, and the size of the transformer.
On a 3 phase meter, when ABC all light up, does it mean you have full voltage?
No. If a transformer fuse is blown (one leg dead), the voltage will feed through the transformer coils which will complete the circuit, but won't give full voltage.
Why may you find 2 single phase meters on a residence or a single phase meter and a 3 phase meter on a business?
In the past, residences had a different rate for water heaters and lights, and businesses had different rates for motor-loads (3ph) and lights (1ph), thus 2 different meters.
Can a new customer connect to the line side of CTs of another customer if a building already has 6 risers?
No. CT lateral owed by the other customer. No connecting to another customers equip. Plus, the CT lateral was sized for their load only.
Can a 20 amp breaker handle up to 20 amps only?
Breakers are rated for 20% over their stated amperage.
What is Cordova's rule of thumb for turnoffs?
Kill the hots on the load side of the meter.
Can a customer have the point of attachment on the roof for a riser?
No. BB states must be on wall, plus 18" min above roofline.
For suicide housings, what must be in place prior to bypassing? Why?
Plastic shield so that the jumpers don't touch the pot clips of the meter. If not in place, kill load, then remove meter.
Why don't we allow power banks? (3w3ph)
Why to we require a N to the line side of the meter if the customer doesn't need it?
For metering purposes. Meter won't work without the N.
How can you remove an OH temp if it has become to rickety to do safely with a ladder?
Knock it over.
Why don't we write up closed loop irregularities if the meter has been put back?
Because the customer will be charged a $50 CL fee and be double billed. (Actual use, plus estimate based on last reading)
Why don't we allow customers to access pulses directly out of a DR87?
Because the LMR is customer owned and prevents customer from accessing the meter directly (has a one way feed)
Why don't we want a customer to reinstall the meter on rewires?
May be the wrong meter for the new service and they may use improper connectors.
What is "master metering"?
- On apartment buildings, they can use 1 master meter instead of individual residential meters up to 4,000amps.
- Some cities will make them install self-owned individual meters as well. They can't charge more than we charge. Some do a flat rate often based on apt square footage.
- Not allowed to have a separate house meter!