Washington electrical administration test

[jst442]

I can't seem to pass the admin test. Today was the second time I've failed missing it by 1 question today. I ve studied and can do a one family and multifamily dwelling super easy and fast. The ones I think I got wrong are the 2 duplex questions, the motor load calculation and the manufacturer facility.
The 2 duplex questions I did them as a one family home and added then together at the end on the total VA. And seemed like none of the answers were close enough. So not sure if I do it as a multifamily or if there is a special code I don't see on a 2 family calculation.
On the motor load calculation it seemed very simple but my answer was way more than answers provided. The question was " there is a 15hp, 2-10hp, and a 5hp periodic 15min motor. All at 480. What is the feeder overcurrent device if using a inverse time breaker?" I got all the ampre for each motor and I multiplied the largest motor by1.25(15hp) and than did the deduction for the 5hp(90%) than added it all together than multiplied it by250%. My answers was way larger than all the answers provided.
Lastly is a non dwelling question (manufacturer facility) . The question was something like " 2 manufacturer share the same building, one building is 4000sqft with a 3hp pump, 1500w micro, 28 outlets, 15ft of show window, 15kw heater and 30a 240 ac. 4.5kw water heater.
The other unit was 15000sq ft, 40 outlets, 25 ft window show lighting, micro. 50kw heat. And some other ones I can't remember. Is there a certain way to do a 2 tenant building that I can't find? I did them as a separate and added them together just as the duplex family homes.
Thanks for the reply and sorry its so long

 

[charlie b]

Courage, my friend. It took me more than one try to pass that exam.

I don't have the time to dig into your questions. I will say that the duplex and manufacturing facility calculations would depend on whether you are calculating a single service for both of the duplex units or a single service for both manufacturing facilities. Your post was not clear on that point.

I will say that I believe a duplex is a multi-family unit. Check the article 100 definitions to be certain.

 

[tom baker]

WA exam questions are copyright protected so you should not post. Do you want me to delete specifics?

 

[jst442]

WA exam questions are copyright protected so you should not post. Do you want me to delete specifics?

Yes thank you I didn't know

 

[jst442]

Courage, my friend. It took me more than one try to pass that exam.

I don't have the time to dig into your questions. I will say that the duplex and manufacturing facility calculations would depend on whether you are calculating a single service for both of the duplex units or a single service for both manufacturing facilities. Your post was not clear on that point.

I will say that I believe a duplex is a multi-family unit. Check the article 100 definitions to be certain.

A two family on one service. For 3 of the question.

 

[letgomywago]

Get a tom Henry's load calc book and you can bring it with you. They will try and get you with the heat vs ac loads and the oven/cook tops. Also if it's to be done as an optional remember to check for the exception of doing it as a triplex of identical units.

 

[jst442]

Get a tom Henry's load calc book and you can bring it with you. They will try and get you with the heat vs ac loads and the oven/cook tops. Also if it's to be done as an optional remember to check for the exception of doing it as a triplex of identical units.

Thank you. I will get it right now

 

[tortuga]

The ones I think I got wrong are the 2 duplex questions,

2 duplexes on one service would be a trick question that's 4 dwelling units, you use the multi family calc.
But I think you just mean a duplex? We need to be clear on that.
Presuming its a duplex:

The 2 duplex questions I did them as a one family home and added then together at the end on the total VA.

Did the question ask you for the optional or the general duplex calc?
A general calc (220.40) can always be used for a duplex unless the question specified optional.
The optional as described in 220.82 is for only one dwelling unit so that would be wrong.
the optional for a duplex is in 220.85 'two dwelling units'.

And seemed like none of the answers were close enough. So not sure if I do it as a multifamily or if there is a special code I don't see on a 2 family calculation.

If its just a duplex none of the study guides I know of cover that much.
here is how I do a 220.85 calc :
Step 1 do a 220.40 (general) calc
Step 2 then combine the 2 units into one jumbo unit in a 220.84(C) calc
Step 3 increase this value by 50% to create 3 identical 'ghost' units.
Step 4 apply a 45% demand factor
[ Steps 3 & 4 can be distilled down to a 67.5% demand factor of the step 2 value. ]
Step 5 use the lesser of the 220.40 and the 220.85 values.

 

[jst442]

2 duplexes on one service would be a trick question that's 4 dwelling units, you use the multi family calc.
But I think you just mean a duplex? We need to be clear on that.
Presuming its a duplex:

Did the question ask you for the optional or the general duplex calc?
A general calc (220.40) can always be used for a duplex unless the question specified optional.
The optional as described in 220.82 is for only one dwelling unit so that would be wrong.
the optional for a duplex is in 220.85 'two dwelling units'.


If its just a duplex none of the study guides I know of cover that much.
here is how I do a 220.85 calc :
Step 1 do a 220.40 (general) calc
Step 2 then combine the 2 units into one jumbo unit in a 220.84(C) calc
Step 3 increase this value by 50% to create 3 identical 'ghost' units.
Step 4 apply a 45% demand factor
[ Steps 3 & 4 can be distilled down to a 67.5% demand factor of the step 2 value. ]
Step 5 use the lesser of the 220.40 and the 220.85 values.

I'm sorry what I meant was I had 2 separate questions on duplex dwellings. Basically 1 of the 2 questions said a duplex dwellings 120/240v has etc etc etc what is the total ampre load for the service. Not the overcurrent just the total ampre of the 2. I couldn't find anything on deduct for 2 family (duplex) so I did them separately.

 

[jst442]

Courage, my friend. It took me more than one try to pass that exam.

I don't have the time to dig into your questions. I will say that the duplex and manufacturing facility calculations would depend on whether you are calculating a single service for both of the duplex units or a single service for both manufacturing facilities. Your post was not clear on that point.

I will say that I believe a duplex is a multi-family unit. Check the article 100 definitions to be certain.

Thank you I will try again. I almost had it. Just irritating because it has no relevance to anything I'll ever do in wa.

 

[jst442]

Did the question ask you for the optional or the general duplex calc?

General

 

[jst442]

the optional for a duplex is in 220.85 'two dwelling units'.

I'll look at the reference tomorrow on optional. It may well have been the optional method.

 

[tom baker]

Thank you I will try again. I almost had it. Just irritating because it has no relevance to anything I'll ever do in wa.

You are tested on your scope of work, not what you do. For example a residential electrician has test questions on hazardous locations since they can do multi family occupations.

 

[electrofelon]

WA exam questions are copyright protected so you should not post. Do you want me to delete specifics?

Just out of curiosity Tom, isn't the NEC copyrighted also? We paste direct passages of that all the time, why is that ok but a rough recollection of a test question is not? (Genuinely curious, not being snarky).

 

[electrofelon]

The duplex question on the test is infamous and has come up on the forum several times.

Think about it this way:. It doesn't matter if a service feeds multiple units or tenants, you would treat everything the service serves for the service calc. Think about it:. If there is some sort of demand factor, why would having those loads split across separate tenants for calculating purposes make sense?

 

[tortuga]

Just irritating because it has no relevance to anything I'll ever do in wa.

I see them all the time, with housing costs going sky high and housing units in short supply more and more people are building these 'tiny homes', 'mother inlaw' units, converting garages or building 'accessory dwelling units' (ADU).
Here in Oregon the state had to step in and deal with the towns that had overly restrictive zoning prohibiting ADU's.
I here its similar in Washington.
Most of these that I see do not get a separate service,
so then you suddenly have the load of two dwelling units on a single service.

 

[tortuga]

Just to add a little more of an example:
For the two family optional your summing up all of the following the items (1)-(5) under 220.84(C):

1. Add up the total square feet of both units and figure 3 VA per square foot.
2. 1500 VA for each Kitchen Appliance and each laundry circuit If the question does not specify the number of small appliance circuits, figure two kitchen circuits for each unit. If it does not mention a laundry area there is no laundry circuit [210.52(F)].
3. From both units all the nameplates of the following:
   1. All Appliances that are fastened in place or on a dedicated circuit etc.
   2. Ranges, wall-mounted ovens, counter-mounted cooking units at namplate, only if specified in the question. If namplate is not specified use 8kW as per 220.84(A) Exception.
   3. Electric Clothes dryer namplates only if stated in the question.
   4. Water heater namplate only if specified in the question.
4. VA of motors, if the motor is given in only HP you need to use the table 430.248 to get the amps and 220.6 for voltage.
5. Sum up the above.
6. Multiply that total by 1.5 to create 3 'ghost units' of equal size.
7. Apply the 45% demand factor.

Effectively steps 6 and 7 apply a 67.5% demand factor to the sum.

 

[tom baker]

Just out of curiosity Tom, isn't the NEC copyrighted also? We paste direct passages of that all the time, why is that ok but a rough recollection of a test question is not? (Genuinely curious, not being snarky).

Good question. There were instructors who paid electricians to take the test and afterwords write up what they could remember for the instructor. This shoes the value in being an electrician and how some are motivated to cheat. By the way there is a fine associated with copying test questions so it’s more than a copyright issue

 

[tom baker]

Passing the electrician or admin test means studying 10-20 hours per week and working 100 questions (per Mike Holt)

 

[electrofelon]

Good question. There were instructors who paid electricians to take the test and afterwords write up what they could remember for the instructor. This shoes the value in being an electrician and how some are motivated to cheat. By the way there is a fine associated with copying test questions so it’s more than a copyright issue

Certainly I don't support cheating, but I also don't like being told that there is a law against something when there may not be. Do you know this supposed law? I am skeptical that in America it's illegal to "copy" a test question.