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How to wire Intermatic T103 and T104 timers

VERY IMPORTANT: Understand that in US residential wiring the WHITE wire is _NOT_ ALWAYS_ the neutral wire. Additionally, prior to 1999 the National Electric Code (NEC) did not require that these white wires be re-identified with black tape or similar means when used for purposes other than neutral. The white wire is sometimes used as a hot, especially when wiring Intermatic T103 and T104 timers.

Also understand that the WHITE neutral wire and the bare (or green) equipment grounding wire are connected together ONLY at the main electric power panel and must _never_be connected together _again_. Once those two wires leave the main electric panel, the WHITE neutral wire must _always_ remain insulated from the bare or green equipment grounding wire. This is very important for safety considerations.

If your wiring is very old and does not have a bare equipment grounding conductor, you _must_ protect the circuit with a GFCI (Ground Fault Circuit Interupter). GFCI wiring is not difficult but is beyond the scope of this post.

DETERMINE WHAT CABLE YOU HAVE:
Usually one will find one of the three following scenarios for the incoming supply cables when wiring a T103 or T104 Intermatic timer:

1...A 120 volt cable with 3 wires: black, white, and bare. The black is LINE (hot), white is neutral and bare is equipment grounding. Black to white is 120 volts. This scenario can be used with the T103, but not the T104.

2...A 240 volt cable with 3 wires: black, white, and bare. The black is LINE(hot), the WHITE is LINE (HOT), and the bare is equipment grounding. Black to white is 240 volts. This scenario is used with the T104 ONLY.

3...A 120/240 volt cable with 4 wires: Black, red, white, and bare. The black and red are (LINE) hot, white is neutral and bare is equipment grounding. Black to red is 240 volts. Black to white is 120 volts. Red to white is 120 volts. This scenario can be used with either the T103 or the T104.

The only difference between the T103 and the T104 is the timer motor voltage rating. The T103 uses a 120 volt timer motor and the T104 uses a 240 volt timer motor. The T103 timer motor is connected to terminal "A" and terminal #3 during manufacturing. The T104 timer motor is connected to terminal #1 and terminal 3# at the factory.

Also, when connecting the bare or green wires to the "GR" terminal, it is best to wirenut the wires together with a pigtail, then connect the pigtail to the "GR" (GRound) terminal, WHICH IS THE GREEN SCREW ON THE LOWER PART OF THE CASE.

WIRING THE TIMER:
The wiring diagram for the T103 is here:
http://www.progressive-growth.com/wiring/T103.pdf
___________________________________________________________________
WIRING THE T103 USING AN INCOMING 120/240 VOLT CABLE WITH 4 WIRES (scenario #3):

Incoming (LINE) wires from 240 volt circuit breaker:
Connect the black (LINE)(hot) wire to terminal #1. Connect the red (LINE) (hot) wire to terminal #3. Connect the white (neutral in this case) wire to terminal "A".
Connect the bare equipment grounding wire to the "GR" terminal, which is the green screw on the case.

Outgoing wires to 240 volt load:
Connect one (hot) wire to terminal #2 and the other (hot) wire to terminal #4. The bare or green wire goes to the "GR" terminal.
___________________________________________________________________
WIRING THE T103 USING AN INCOMING _120_ VOLT CABLE WITH 3 WIRES (scenario #1):

Incoming wires from 120 volt breaker or source:
Black (LINE) to terminal #3. White (neutral) to terminal "A". Bare to the "GR" terminal.

Terminals #1 and #2 are NOT used in this case.

Outgoing wires to 120 volt load(s):
Black(hot) to terminal #4. White(neutral) to terminal "A". Bare to the "GR" terminal.

The wiring diagram for the T104 is here:
http://www.progressive-growth.com/wiring/T104.pdf
______________________________________________________________
WIRING THE T104 USING AN INCOMING 240 VOLT CABLE WITH 3 WIRES (scenario #2):

Incoming (LINE) wires from breaker:
Connect the black (LINE) (hot) wire to terminal #1. Connect the white (LINE) (hot in this case) to terminal #3. Connect the bare wire to the "GR" terminal.

The "A" terminal is _NOT_ used.

Outgoing wires to load:
Connect one (hot) wire to terminal #2 and the other (hot) wire to terminal #4. Connect the bare or green wire to terminal "GR".

The "A" terminal is _NOT_ used.
______________________________________________________________
WIRING THE T104 USING AN INCOMING 240 VOLT CABLE WITH 4 WIRES:
Same as above, except the white wire is not used. Just tape or wirenut it off.
Comment by gotgeek2, posted on Jan 08, 2010ckuzkuz, I'm a licensed master electrician in 2 states with 30 years in the trade. I've installed a lot of Intermatic timers over the years. I wrote this tip because I saw that a lot of folks were having problems wiring them.

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Electrical needs


Red and or white should be active, black should be. Neutral and green should be earth. Get some one who understands it before you fry yourself.

Mar 06, 2014 | Amana AKT3630 Electric Cooktop

5 Answers

How to wire Intermatic T103 and T104 timers


Thanks GotGeek2! I needed the info in WIRING THE T103 USING AN INCOMING 120/240 VOLT CABLE WITH 4 WIRES (scenario #3). Your's is a very clear, precise, and generous posting. Zybercom

Dec 28, 2009 | Hardware & Accessories

1 Answer

Can a tork timer 1101 be used to control a 240 volt pool pump motor by controlling only 1 lead of the motor thus having the other lead hot all the time?


Yes: 240 volt can be controlled by turning off 1 hot leg of 240V circuit.
But the tork 101 clock motor still requires 120Volts (unless you buy a tork 240volt 201 clock motor to replace the 120volt 101)

Copy following links for handy resource and wiring diagram:
http://waterheatertimer.org/Tork-timers-and-manuals.html#1101

http://waterheatertimer.org/images/Tork-1101-wired-to-control-240.jpg

In the wiring diagram above, it shows white neutral wire running to Tork 1101 timer terminal 2. Bring this white neutral wire from any nearby 120volt outlet.
In event that you do not have this white neutral wire, you can connect ground wire to terminal 2 and that will give 120volts to the 101 clock motor.
Completing circuit to clock motor using ground wire is violation of national electric code for many reasons, however the tiny clock motor only draws 3 watts, and you will remember to bring a white neutral wire to this timer at later date so you can sleep better at night.

Additional resources:
http://waterheatertimer.org/See-inside-main-breaker-box.html

http://waterheatertimer.org/images/Inside-Main-Breaker-Box-12.jpg

Gene
h

Aug 27, 2013 | Hardware & Accessories

1 Answer

what does "open neutral" mean?


The "neutral" wire in home wiring is always the "white" wire. The hot line is always the "black" wire or in the case of a multiple conductor, can be just about any color but white or green. Green is circuit ground, the nasty 3rd pin on the plugs we use, but a very important safety feature.
When you have an "open neutral" reading it means that the "white" wire has come loose some place in your wiring. A broken or loose wire is referred to as an "open" in electrical terms. I assume you are plugging an outlet tester in and get this indication. It may just be in the outlet you are testing or someplace else between the outlet and the circuit breaker.

Sep 12, 2010 | Sperry Instruments Measuring Tools &...

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What is the difference between the red/black wire and the blue/white wire.


    How to Know Wire Colors
  1. Step 1 In most home-wiring applications, the circuit features one black wire, one white wire and a green or non-insulated ground wire. On this type of circuit the black wire is delivering the voltage and the white is acting as the neutral. The circuit has to have each in order to be complete. In some cases a white wire may be used as a hot feed. When this occurs it is commonplace for the white wire to have a strip of black electrical tape around the insulation to signify that it is being used as a hot wire.
  2. Step 2 You may notice a red wire from time to time. The red wire has a couple of responsibilities: It can be a second circuit, sharing the neutral with the circuit fed by the black wire or it can be a traveler, as used in a three-way switch configuration. Additional conductors like the one found in 4-wire electrical wire may be colored blue.
  3. Step 3 While some 240-volt circuits use different colored wires including orange, yellow, brown and gray, they are not typically found in the residential home, so we will go into those applications in another article.

Feb 05, 2010 | Yamaha NS-A60X Main / Stereo Speaker

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