vault backup: 2025-11-03 17:15:51
This commit is contained in:
+1
-95
@@ -119,101 +119,7 @@ either for spec requirements or conduit fill considerations.
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## Voltage Drop
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> [!info] Ohm's Law
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>
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> $$
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> V = I \times R, \quad R = \frac{V}{I}, \quad I = \frac{V}{R}
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> $$
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### Step 1: Effective Impedance $Z$
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$$
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Z = R \cos(\theta) + X \sin(\theta)
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$$
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where
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* $Z$ = Effective impedance
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* $R$ = AC resistance
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* $X$ = Reactance
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* $\theta$ = Power factor angle = $\arccos(PF)$
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#### Parallel Runs
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The equivalent resistance of parallel resistances is given by
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$$
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\frac{1}{R_{\text{eq}}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + \dots + \frac{1}{R_n}
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$$
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For $n$ parallel resistances of value $R$
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$$
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\begin{align*}
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\frac{1}{R_{\text{eq}}} &= n \times \left(\frac{1}{R}\right) \\
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&= \frac{n}{R} \\
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R_{\text{eq}} &= \frac{R}{n}
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\end{align*}
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$$
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### Step 2: Voltage Drop
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> [!important]
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> This section assumes a 3-phase
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> 208Y/120V or 480Y/277V voltage system
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> [!info] 3-Phase Voltage
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>
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> $$
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> V_{L} = \sqrt{3} \times V_{P}, \quad V_{P} = \frac{V_{L}}{\sqrt{3}}
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> $$
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3% allowable voltage drop for a 120V line-to-neutral load:
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$$
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\text{Max} \Delta V = 0.03 \times 120 \text{V}_{P} = 3.6 \text{V}_{P}
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$$
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3% allowable voltage drop for a 208V line-to-line load:
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$$
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\text{Max} \Delta V = 0.03 \times 208 \text{V}_{L} = 6.24 \text{V}_{L}
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$$
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#### Line to Neutral Loads
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$$
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\Delta V_{P} = I \times Z \times 2L
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$$
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#### Line to Line Loads
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$$
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\Delta V_{L} = \sqrt{3} \times \left( I \times Z \times 2L \right)
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$$
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#### 3-Phase Loads
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$$
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\Delta V_{3\phi} = \sqrt{3} \times \left( I \times Z \times L \right)
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$$
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where
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* $\Delta V$ = Voltage drop in volts ($V$)
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* $I$ = Current in amperes ($A$)
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* $L$ = Length of wire one way in feet ($\text{ft}$)
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> [!important]
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> "Current" is not the OCPD rating,
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> but the actual load.
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***
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It is often more useful to know the maximum length
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a certain wiring configuration is suitable for.
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$$
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L = \frac{ \Delta V }{ I \times M } \times \frac{1}{Z}
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$$
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[[voltage-drop]]
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## Transformers
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@@ -0,0 +1,33 @@
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---
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id:
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aliases: []
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tags:
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- authorship/original
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- destiny/permanent
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- topic/organization
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title: Individual Ability
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---
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# Individual Ability
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**Effort is the smallest part of improvement.**
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This note is about practical ability.
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For discussion of how others _perceive_ ability,
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see [[professionalism]].
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Individuals differ in **learning rate** and **capacity for familiarity**.
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Whether nature or nurture is to blame,
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there is little an adult can do to move those needles.
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Making the most of the resources you have
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requires developing effective coping mechanisms
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(like [[notetaking]]).
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To gain and maintain skill is time consuming.
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The barrier to greater professional skill
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for most people is **responsibility**.
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## Capacity for Familiarity
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There is a practical limit to the mind's "shelf space".
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It's not only a question of experience or exposure,
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familiarity requires maintenance.
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@@ -0,0 +1,21 @@
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---
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id:
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aliases: []
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tags:
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- authorship/original
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- destiny/permanent
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- topic/organization
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title: Notetaking
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---
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# Notetaking
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## `TALK`
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This note is intended for
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* why one should want to take notes,
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* what good notes should do
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There are bad media for notetaking
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* print
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+1
-1
@@ -28,4 +28,4 @@ $$
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P &= I \times (I \times R) \\
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&= I^{2}R
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\end{align*}
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$$
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$$
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@@ -0,0 +1,54 @@
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---
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id:
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aliases: []
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tags:
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- authorship/original
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- destiny/permanent
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- topic/organization
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title: Professionalism
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---
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# Professionalism
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<!-- TODO: -->
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## `TALK`
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I want to use this note to talk about
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what makes an expert and
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what makes an "expert".
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* imposter syndrome
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* effectiveness vs productivity
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* traits valued by employers/clients
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* being a "salesman" of your abilities
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### Being a Salesman of Your Ability
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To "sell" something in the sales sense
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is to make it more appealing _without changing it_.
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A cynic might call this lying.
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A more fair take is that people generally present their ability as less than it is.
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I suspect that the most knowledgeable
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and technically effective practitioners of any field
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are not known to be such.
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To be a salesman of some ability
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is a deviation from specialization in that ability.
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Every bit of [[individual-ability#Capacity for Familiarity|capacity]]
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devoted to salesmanship
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is a bit less to the skill itself.
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> [!example]
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> Mike Holt has a better grasp on code than most,
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> but there are likely hundreds better than him
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> specifically in that aspect.
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>
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> It is his salesmanship, his visible confidence in his ability,
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> that makes up the difference.
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### Optics, or Playing the Game
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#### Example: Notetaking
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note-takers always look more valuable than they would otherwise.
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@@ -0,0 +1,62 @@
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---
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id:
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aliases: []
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tags:
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- authorship/original
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- destiny/permanent
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- status/incomplete
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- topic/organization
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- type/guide
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title: Resolving Process Uncertainty
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---
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# Resolving Process Uncertainty
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## Process Uncertainty Resolution Steps
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1. **Check your [[#Writing Process Notes|notes]]**
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2. **[[#Asking Process Questions|Ask]] a ==peer== whose answers you trust**
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3. **Ask your immediate supervisor**
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Only escalate if you are still uncertain.
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## Writing Process Notes
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<!-- TODO: -->
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### `TALK`
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Taking notes has many benefits,
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many of which I would not list as such
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* **deferring responsibility:**
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* **optics:**
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note-takers always look more valuable than they would otherwise.
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### Citation
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When you get an answer to a [[#Asking Process Questions|question]],
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or otherwise get some useful direction
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that you expect to use later,
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You should add it to your notes as soon as possible.
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With any direction you should include:
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* **who** said it,
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* **when** they said it, and
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* **what** it was in reference to.
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```md
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> [!quote]
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```
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## Asking Process Questions
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Ask your question as succinctly as possible **first**,
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provide background or complications **after**.
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Prepare for any obvious clarifying questions.
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### Choosing Your Target
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<!-- TODO: -->
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+107
@@ -0,0 +1,107 @@
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---
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id:
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aliases: []
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tags:
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- authorship/original
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- destiny/permanent
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- status/incomplete
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- topic/construction/electrical
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title: Voltage Drop
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---
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# Voltage Drop
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> [!info] Ohm's Law
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>
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> $$
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> V = I \times R, \quad R = \frac{V}{I}, \quad I = \frac{V}{R}
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> $$
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## Step 1: Effective Impedance $Z$
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$$
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Z = R \cos(\theta) + X \sin(\theta)
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$$
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where
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* $Z$ = Effective impedance
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* $R$ = AC resistance
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* $X$ = Reactance
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* $\theta$ = Power factor angle = $\arccos(PF)$
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### Parallel Runs
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The equivalent resistance of parallel resistances is given by
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$$
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\frac{1}{R_{\text{eq}}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + \dots + \frac{1}{R_n}
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$$
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For $n$ parallel resistances of value $R$
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$$
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\begin{align*}
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\frac{1}{R_{\text{eq}}} &= n \times \left(\frac{1}{R}\right) \\
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&= \frac{n}{R} \\
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R_{\text{eq}} &= \frac{R}{n}
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\end{align*}
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$$
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## Step 2: Voltage Drop
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> [!important]
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> This section assumes a 3-phase
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> 208Y/120V or 480Y/277V voltage system
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> [!info] 3-Phase Voltage
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>
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> $$
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> V_{L} = \sqrt{3} \times V_{P}, \quad V_{P} = \frac{V_{L}}{\sqrt{3}}
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> $$
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3% allowable voltage drop for a 120V line-to-neutral load:
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$$
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\text{Max}\ \Delta V = 0.03 \times 120 \text{V}_{P} = 3.60 \text{V}_{P}
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$$
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3% allowable voltage drop for a 208V line-to-line load:
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$$
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\text{Max}\ \Delta V = 0.03 \times 208 \text{V}_{L} = 6.24 \text{V}_{L}
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$$
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### Line to Neutral Loads
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$$
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\Delta V_{P} = I \times Z \times 2L
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$$
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### Line to Line Loads
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$$
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\Delta V_{L} = I \times Z \times 2L
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$$
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### 3-Phase Loads
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$$
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\Delta V_{3\phi} = \sqrt{3} \times \left( I \times Z \times L )
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$$
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where
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* $\Delta V$ = Voltage drop in volts ($V$)
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* $I$ = Current in amperes ($A$)
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* $L$ = Length of wire one way in feet ($\text{ft}$)
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|
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> [!important]
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> "Current" is not the OCPD rating,
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> but the actual load.
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***
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It is often more useful to know the maximum length
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a certain wiring configuration is suitable for.
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$$
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L = \frac{ \Delta V }{ I \times M } \times \frac{1}{Z}
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$$
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@@ -0,0 +1,29 @@
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---
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||||
id:
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aliases: []
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tags:
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- authorship/original
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- destiny/fleeting
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- type/task
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title: Write More Philosophy
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---
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# Write More Philosophy
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I've been making steady progress on the factual content of [[this-notebook]],
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however it's getting drier with every `#type/encyclopedia`.
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I want to write more opinionated, less universally agreeable pieces.
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## Recent Additions
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What one _should_ do with their life:
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* [[notetaking]]
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What traits people _should_ value:
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* [[professionalism]]
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What is _wrong_ but widely accepted:
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* [[individual-ability]]
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