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DC safety switches
DC safety switch Non-fusible
DC safety switch 250 Volt
DC safety switch outdoor

Buy: $135
3-pole / outdoor/ 30 amp DC/ non-fuse
30 amp DC 240 volt outdoor
Grounding lugs at Amazon<
Difference between AC and DC safety switch wiring How to wire safety switch
DC safety switch fusible
DC safety switch 250 Volt
DC safety switch indoor

Buy: $335
3-pole / outdoor/ 30 amp DC/ fusable
30 amp DC safety switch 30 amp DC safety switch/ fusible/ outdoor
Heavy Duty 250 V Dc Voltage; 30 Ampere
Use 10 gauge wire
Do not use fuses larger than amp rating of wire
Buy:
Square D 30 amp DC HU361RB
30 amp DC 240 volt 600 Volt

Resource:
Generic: How to wire safety switch
Convert AC water heater to DC water heater
DC relays for solar power
DC safety switch wiring/ pdf
Schneider safety switch wiring for DC/ pdf
Schneider safety switches/ pdf
30 amp DC safety switch 60 amp DC safety switch/ fusible/ outdoor
Heavy Duty 250 V Dc Voltage; 60 Ampere
Use 10 gauge wire with 30 amp fuse
Use 6 gauge wire with 60 amp fuse
Buy:
Square D 60 amp DC H222AWK


Resource:
Generic: How to wire safety switch
Convert AC water heater to DC water heater
DC relays for solar power
DC safety switch wiring/ pdf
Schneider safety switch wiring for DC/ pdf
Schneider safety switches/ pdf
Class R fuses
600 volt AC @ 30 amp fuse/ 300 volt DC @ 15 amp
600 volt AC  @ 600 amp/ 120 volt DC @ 60 amp
6000 volt AC @ 6000 amp/ 300 volt DC 2000 amp
Time delay fuse passes surge currents without sacrifice short circuit limitation
AC rating for 200 kA is reduced to 20 kA for DC
kA is max surge capability... if too much surge is on the fuse, the fuse will not trip and fuse can melt onto the contacts, feeding high voltage into the wire causing possible fire

How to wire safety switch
Bussman
Buy
60 amp DC cartridge fuse
50 amp DC cartridge fuse
40 amp DC cartridge fuse
35 amp DC cartridge fuse
30 amp DC cartridge fuse
25 amp DC cartridge fuse
20 amp DC cartridge fuse

70 amp DC cartridge fuse
90 amp DC cartridge fuse
80 amp DC cartridge fuse
125 amp DC cartridge fuse
150 amp DC cartridge fuse
175 amp DC cartridge fuse
200 amp DC cartridge fuse
225 amp DC cartridge fuse
250 amp DC cartridge fuse
300 amp DC cartridge fuse
350 amp DC cartridge fuse
600 amp DC cartridge fuse
Buy
Class R fuses at Amazon
30 amp Cartridge fuse
60 amp Cartridge fuse
Busman fuses at Amazon

Resource:
Busman fuses/ pdf
PV safety switch Example DC safety switch for solar array
Use fused or non-fused
This is one way to use safety switch
Purpose of safety switch is to ensure all power is OFF
The handle is clearly visible and can be latched in place
Locate safety switch in plain sight so people can clearly identity when power is OFF
Remember, a solar panel will produce electricity each time it is exposed to light.
You can get shock from solar panel when panel is exposed to sun.
The array and safety switch must be wired at night

The strings can be combined before connecting to safety switch... match total volts and amps with safety switch rating and with fuse rating
When three panels are wired together, the positive wire connects to negative wire to make a string.
Solar panels are like batteries.
When three panels are connected in series, or in a string, then voltage increases with each additional panel, but amperage stays the same.
Illustration shows 3 strings with 3 panels in each string.
If the strings are combined together in parallel, then the voltage stays the same but amperage increases.
Maximum voltage for wire and safety switch is 600 volts AC/ 300 volt DC

Resources:

Calculate volts and amps for array/ How to set up array
DC safety switch wiring/ pdf
DC safety switch 100 amp Non-fusible/ outdoor
250 VDC 30 amp
Buy:
100 amp non-fusible/ outdoor/ at Amazon

Resource:
Generic: How to wire safety switch
Convert AC water heater to DC water heater
DC relays for solar power
How to wire safety switch
DC to DC relay   DC power relay
250VDC    25 amp                        400VDC  200 amp

These are the big boys
Connect big volts and amps to the contacts
Operate the coil using 12-24 Volt DC
DC to DC relay/ mechanical type
240 Volt DC power relay /26 amp to 200 amp DC
Full on-off contacts/ 12 or 24 volt DC coil
250 volt / 25 amp DC load
250V x 25 amp = 6250 watt
Connect 12 or 24 volt DC to terminals 3-4;
Connect load to terminals 1-2

Buy:
Electromechanical DC-DC G9EB-1 relay
G9EB-1-B-DC24
24 VDC coil and 400 VDC/ 200 amp contacts
Omron relay at online
Fuseholder

Resources:
Omron-DC-DC-relay-Datasheet
Omron DC-DC pdf
DC power relay spec sheet
Convert AC water heater to DC water heater
DC relays for solar power
DC arc extinction/ controlling high voltage DC
"the higher the number of contacts opening the circuit, the higher the breaking capacity of the circuit-breaker.
This means that, when the voltage rises, it is necessary to increase the number of current interruptions in series, so that a rise in the arc voltage is obtained and consequently a number of poles for breaking operation suitable to the fault level."
What this quote means: A DC circuit breaker or any DC switchgear must have multiple contacts that disconnect as illustrated in diagrams below
You want to increase the number of contact points, so the arc from DC power can be extinguished
AC electricity oscillates.
The voltage rises and falls.
60 times each second, the voltages drops to zero.
Of course you notice this when grabbing a hot wire, because there is voltage on the line.
There is a difference when choosing switchgear.
Each time a switch is thrown, there is an arc (or spark) that continues to jump between the contact points of the switch.
With AC power, the arc is 'extinguished' more easily because voltage reaches zero at some point and the arc stops.

With DC power, the arc is more difficult to extinguish.
DC never reaches zero volts, because it doesn't change direction... it doesn't oscillate.... and so electrons keep piling against one another, forcing the front ones to jump across the switch contacts.
So switchgear must be rated for DC.
Using AC switchgear will sometimes work, BUT careful attention must be paid to rating label.
Each switch has a rating label or rating specifications.
For example a switch might be rated 240 volt 30 amp AC, but only rated 48 volt 3 amp DC.
If a device does not show DC rating, then assume it is not sufficient for DC application, and might be fire hazard.
"the higher is the number of contacts opening the circuit, the higher is the breaking capacity of the circuit-breaker.
This means that, when the voltage rises, it is necessary to increase the number of current interruptions in series, so that a rise in the arc voltage is obtained and consequently a number of poles for breaking operation suitable to the fault level."
So a DC circuit breaker or any DC switchgear must have multiple contacts that disconnect as illustrated in diagram below.
Resource:
DC arc extinction .pdf
Read about difference between AC and DC
DC contactor3-pole contactor wired for DC loads
The higher the number of contacts opening the circuit, the higher the breaking capacity
DC direct current is different than AC alternating current.

Illustration shows one method of extinguishing DC arc using 3-pole contactor. The circuit has 3 parallel switches on the positive wire, thus helping to stop the arc better than 1 switch.
If a 4-pole contactor is used, 3 poles can be used to turn off Positive, and 1 pole to turn off Negative.
To help eliminate arcs, add a resistor in parallel with inductive winding. Example of inductive winding is motor load

When high voltage DC is turned off, the electrons keep pushing because the voltage never reaches zero.
Result: DC voltage causes arc or spark or heat that is difficult to stop. Basically the electrons keep piling up and pushing the arc across the points of the contactor.
DC switchgear must be rated for DC voltages, and be capable of extinguishing DC arc.


Buy:
3-pole contactors

Resources:
Solar contactor/ pdf
DC relays for solar
DC contactor wiring diagrams/ pdf
What is 3-phase electricity
Can AC circuit breaker be used for DC
Use only 600 volt wire.
Lamp cord, extension cords are not rated 600 volt.
Use copper wire only. Aluminum wire is fire risk and should be avoided or installed by professional.

30 amp breaker use 10 gauge /
120-240 volt 30 amp outlet can be installed on 30 amp breaker only/ use 10 gauge wire ... cannot be connected to 15-20-40 amp breaker.

Orange/ #10 gauge wire, with ground ... 30 amp capacity. Safe maximum: 30 x 80% = 24 amps.
Buy:
10-2 gauge/ 30 amp
10-3/ 30 amp
Southwire electric tools
Yellow 12 gauge 20 amp
120 volt 20 amp outlet can be installed on 20 amp breaker, but not 15 amp breaker/ use 12 ga wire.
... cannot be connected to 30-40 amp breaker. 1

Yellow/ #12 gauge wire, with ground ... 20 amp capacity. Safe maximum 16 amps.
Buy:
12-2 gauge/ 20 amp
12-3/ 20 amp

NMB is house wiring
UF is underground
Rolls of stranded wire
HOOK UP Wires
White 14 gauge 15 amp
120 volt 15 amp outlet, AFCI, GFCI, timer, switch etc can be installed on 15 or 20 amp breaker. Never connect 15 gauge wire to 20-30-40 amp breaker.

White/ #14 gauge wire,  with ground ... 15 amp capacity. Safe maximum 12 amps.
Buy:
14-2 gauge/ 15 amp
14-3/ 15 amp

NMB is house wiring
UF is underground
50-60 amp breaker use 6 gauge /
240 volt 50 outlet can be installed on 50 amp breaker only
6-2 wire
Buy:
6-2 wire
Southwire electric tools
NMB is house wiring
UF is underground
40-50 amp breaker use 8 gauge /
240 volt 40 amp outlet can be installed on 40 or 50 amp breaker only
6-2 wire
Buy:
8-2 wire
Southwire electric tools
NMB is house wiring
UF is underground
     
Copper ground wire.
Every device, load, metal enclosure etc must be grounded. Ground wire must be continuous throughout installation, never switched on-off, never used as a Neutral wire.
Generally ... use same size as other wire in circuit
Buy:
12 gauge copper ground wire
Ground wire
Green ground wire
Ground pigtails
Ground rods/ ground clamps at Amazon
armored cable
Non metallic flexible cables must carry ground wire, but do not have hazard of short circuit causing injury from shock.

Armored steel cable can be used as a grounded connection, and will protect wires from damage. Metal can be energized from an insulation failure.

All conduit ...metal, plastic ... flexible and rigid ... must be attached to structure, and attached to enclosures, boxes.
Movement, damage and deterioration are major cause of electrical failure.
Buy:
Non-metallic flexible conduit
Power whip
Armored cable
Southwire armored cable cutter
Pull boxes
Southwire armored cable cutter
Electrical tools must be insulated.
Always best to disconnect power, but insulation failure, lack of proper grounding, grounded neutral, lack of GFCI, out-of-code wiring, generator operating without transfer switch, and other problems still pose a risk to anyone working on electric power ... even when breaker is off.

Buy:
Electrician tools kits
KLEIN TOOLS
Tools kits
IRWIN tools
KNIPEX

Telephone cable knife
Low Voltage Mounting Bracket for Telephone
Push on wire connectors

Push-on wire connectors in place of twist-on connectors

Buy:
Push on wire connectors Amazon
Red 3P connector for 10-14 gauge wire
Lever connectors for stranded wire at Amazon
HOOK UP Wires

Protect wiring from damage
Use nipper instead of pliers or screwdriver for removing staples (and nails). Do not damage cable or wires inside cable.

-Code says: Cable SHALL BE secured without damage to the outer covering. NEC sec. 336-15
Buy
End cutting nippers at Amazon


Electrically insulated tools
When removing insulation from wire, do NOT score or put cuts on surface of copper wire. Doing so increases resistance and heat on wire and creates possible weak point.
Buy tools:
KLEIN TOOLS
Wire strippers at Amazon
Electric Wire Stripping Machine
Linesman pliers
Utility knife at Amazon
multimeter
Multimeters
Voltage is tested across two separate wires. Ohms or resistance is tested across both ends of same wire. Amperage is tested along one or two points on same wire.
Buy:
Analog multimeter
Multimeters at Amazon
Klein multimeter
Electric testers at Amazon
Clampmeter for testing amp flow on line

GFCI circuit breaker
A GFCI circuit breaker will protect all boxes on circuit.

Circuit must be grounded. Ground wire must be continuous and connected to each piece of equipment.

White wire on circuit breaker must be connected to Neutral busbar inside the breaker panel.

Buy
GFCI circuit breakers
Push down
single-pole breaker
1" wide Push down breaker
Plug-in breaker
Buy single-pole:
Choose from 15 to 60 amp
Eaton CL series
Siemens 15-60 amp

Single-pole tandem breaker
Tandem breakers
Push down
double-pole breaker
2" wide Push down breaker
Plug-in breakers
Buy double-pole:
Choose from 15 to 125 amp
Choose from 15 amp to 200 amp
Eaton CL series circuit breaker
Siemens circuit breaker
Double pole GFCI
Support the economy:
Buy water heaters from my associate links:

50 gallon Gas water heaters at Amazon
40 gallon gas water heaters at Amazon
50 gallon Electric water heaters at Amazon
40 gallon electric water heaters at Amazon
Hybrid / heat pump/ water heaters at Amazon

Resources:
How to install gas water heater
How to install electric water heater
Troubleshoot gas water heater
Troubleshoot electric water heater
Point of use water heaters
Resources:
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Icon gas valve

How to replace water heater element Waste King disposal
How to wire tankless electric


Install point of use water heater
Titan tankless

Contactors/ relays
Type 1 and type 2 surge protection surge protection
Programmable timers

Woods timers
surge protection
Anode rods anode rods
Recirculation system

Tankless recirculation
Point of use water heater
Install and troubleshoot garbage disposal Waste King disposal
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Electronic parts

Industrial supplies

Tools and home improvement

Home and garden

Hayward pool
Pentair pool

Southwire electric
Buy
Tools

DEWALT
Black and Decker
Stanley
SKIL
Makita
Porter-Cable
Bosch

Irwin Hand tools
Klein hand tools
Fluke electrical testing
Dremel hobby tools

Campbell Hausfeld air powered
Tekton automotive

Powerbuilt automotive
Saws and saw blades
box timers Resource:
Compare box timers
DPDT timers
Intermatic
Control water heater w/ Z-wave
Intermatic control centers Resource:
Intermatic control centers: and parts
Digital control centers and parts
Tork control centers and parts
Subpanels
All control centers and parts
Enclosures
programmable timer Resource:
Programmable timers
Countdown timers
Off delay timers
On delay timers
Timer modules
Din rail
Twin & one-shot
Woods
Intermatic
Tork
Low voltage power packs Recirculation systems
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