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How to wire Intermatic T104 and T103 and T101 timers

Including diagrams for T102, T105, T106 timers
T104 & T174 wiring
T103 & T173 wiring
T101 & T171 wiring
T101B wiring


Click link on left ot right to scroll down page to location
T102 & T172 wiring
T105 & T175 wiring
T106 & T176 wiring
T104 manual
T104-50 / 50Hz timer/ same wiring as T104
T10404 manual
T106 manual with NO NC terminals
T10604 manual
T101 manual
T101B manual
T102 manual
T103 manual
T105 manual with NO NC terminals
T100 series sell sheet
T101R24 24Volt CW1570 clock motor


T170 Series has same wiring as T100 Series except T170 has day skipper.
Pool timers have same wiring as shown below

T100 series R = raintight enclosure / example T104R
T100 series M = mechanism only/ example T104M
Pool timer manuals:
T104P201 manual
T104M201 timer manual
T104R201 manual
T104R3 same as T104
T101R3 same as T101
T101R201 manual
T101P201 manual
Firemans switch

Troubleshoot/ and fire safety

Troubleshoot resource:
How to Troubleshoot Intermatic timer

Fire safety resource:
Do not use stranded wire without soldering to make solid end. Stranded wire will come loose and cause arcing.
Use only solid copper wire. Do not use aluminum wire.
Maximum 2 wires under same screw plate.
Do not use 2 different gauge wires under same screw plate.
For more wires, or different gauge wires, attach with wire nut and connect jumper wire to screw plate.
Tighten screws very tight against copper wire.
Keep Door to enclosure closed at all times.
Turn off power before working on wires.

Operation resource:
How to operate and set T104 timer

Close-up photos of T100 series

See up close photos of WH40 (same as T104)
How to maintain T100 series timer
Troubleshoot T100 series timer
T100 series timers/  5 knock-outs
1 on back, 1 on each side and 2 on bottom
Intermatic clock motor
3 watt power consumption

Buy clock motors/ 50 and 60 Hz:

US power grid is 60 Hz
WG1573 208-277V Amazon
WG1570 120V at Amazon
WG1576 480V at Amazon
CW1570 24V at Aplus
50 Hz
WG1574 motor for 50Hz 208-277V Amazon
Order T104-50 timer 208-240V 50 Hz     T104-50 at Amazon
How to replace Intermatic clock motor
Some Intermatic timers are rated both 50-60 Hz and can be used any country worldwide
EH40 30 amp timer is 50-60 Hz
                                     156T1961A tripper                        
Enclosures                       T100 series mechanism          156T1976A tripper

More repair Parts

156T1978A T100 series trippers at Amazon
T100 series parts
T170 series parts
Prevent fires: Never put stranded wire and solid wire under same screw plate. Never mix different wire gauges under same screw plate. Use only copper wire. Observe load ratings for timer and wires, max 40 amp per pole. Keep enclosure door closed to prevent overheating from getting supply of oxygen and growing into fire that can spread to local room.

Intermatic T104P201 Intermatic 156T4042A fireman switch
Fireman's switch
How to wire fireman's switch

T100 series Pool timers

Pool timer manuals
Pool timers have same wiring as T100 series, except with fireman's switch
Fireman's switch is connected to wires from pool heater, and is not wired with electricity inside timer. Pool heater must have fireman switch connections.
PF1112T T104 with freeze thermostat

Control centers/ with T100 series timers

Maximum 15 amp breaker in control centers with circuit breaker
See T104 timer wiring below
Control centers and wiring
How to wire Intermatic Sprinkler timers
How to wire WH40, EH40, EH10, WH21 timers
How to wire Intermatic ET series timers
How to wire Intermatic GM40 and WHQ timers
How to wire T1906, T1905, T1975, T1976 timers
How to wire Intermatic ST01C, Ei600, EJ500 timers
How to wire remote control timer
How to wire 3 phase timer

More Intermatic

See all Intermatic timers
How to wire Intermatic timers
How to wire Intermatic/Malibu timers
How to wire Intermatic FM1 timer
How to wire Intermatic PB300 series timer
How to wire Intermatic whole house surge

T104 Wiring begins here

Applies to T104, T104R/P, T104-50, T104M, WH40, T174, T174R, T17P, T174M, T104R3, T104P201, T104R201, etc  see all models
How do you know if you have T104: Is power connected to double pole circuit breaker?, Are there 5 screw terminals on timer? Are white clock wires on terminals 1 and 3? Is clock motor WG1573?
T104 wiring
Detail below

T104/ T104R / T104P etc
T104 metal indoor at Amazon
T104R metal outdoor box
T104P plastic outdoor
T104 series models/ manuals

T174/ T174R / T174M
With day skipper
T174 metal indoor at Amazon
T174R metal outdoor
T174CR carryover
T174 series models / manuals
Intermatic WH40 timer
WH40 at Amazon
WH40 timer resources
Intermatic T104P201 timer
T104M  mechanism only
T104M at Amazon
T104M at Amazon
T104 series models/ manuals
Intermatic T104P201 timer
T104R201 T104P201 T104R3
T104P201 plastic Amazon
T104R201 metal Amazon
T104R3 metal box
T104P3 plastic box
T104 pool timer models/ manuals
T104M201 mechanism with fireman switch
T104M201/ fireman at Amazon
T104 timer models/ manuals
More parts
T104PCD82 See thru door
T104PCD82 at Amazon
T104 series models/ manuals
Buy T100 series timers/ all models
Intermatic T104
Basic wiring diagram

T-104 timer 240Volts or 208 Volts

Check label on side of water heater for Volts & Watts
This timer can be used for 120V circuit, see below
T104 uses WG1573 clock motor
T104 steel indoor box
T104R steel outdoor box
T104P plastic outdoor box
T104PCD3 see-thru door
All models
T104 manual
T100 series sell sheet

Repair part list
Rreplacement clock motors

How to find Hot wire

See another image of same wiring shown above
Basic wiring diagram

T-104 timer 240 Volts or 208 Volts

Same wiring applies to T174, WH40
and  T174
and  WH40

and T104P201 and T104R201

Add tape to white wire, when using black-and-white wires for 240Volt,
This will notify next electrician that white wire carries power
T104 controls two loads
Larger image

T-104/ Two 240 Volt loads or Two 208 Volt Loads

Move motor leads to terminals A and 1
Turning off 1 Hot wire will turn off 240Volt circuit.
Read difference between 120Volt and 240Volt

If you want both Loads to turn on-off at different times, then you need two timers, or digital timer with two-channel capability such as GM40AVE, GMX2FM2, ET1100, RT1700, P1353
Open following link and use Ctrl+F find feature on browser
Intermatic timers and manuals

240Volt wires can be
Sometimes Red-Red
Should not be White-White
Wire T104 timer for 277 volts
Larger image

T-104 277 Volts

Move motor leads to terminals A and 1

Terminals 3 and 4 are dry (have no voltage) in this configuration, and can be wired to control any voltage, or jumper hot wire between terminals 1 and 3

277 Volt timer can be used to control 3-phase 3-pole contactor
How to install 3-phase timer
Intermatic T102 wiring
T-102 timer is pre-wired for this installation
See more T102 wiring
T104 controls two 277 volt loads
Larger image

T-104/ Two 277 Volt loads

Move motor leads to terminals A and 1
Add jumper from terminal 1 to terminal 3

If you want both Loads to turn on-off at different times, then you need two timers, or digital timer with two-channel capability such as GM40AVE, GMX2FM2, ET1100, RT1700
Open following link and use Ctrl+F find feature on browser
Intermatic timers and manuals

T104 controls any voltage
Larger image

T-104 controls any voltage/ 

Dry terminals

Move motor leads to terminals A and 1
Connect 240 Volt or 277 Volt to A and 1
Connect any voltage to terminals 3 and 4/ SPST

Larger image

T-104 controls any voltage SPST & 240Volt SPST

Move motor leads to terminals A and 1
Connect 240 Volt or 277 Volt to A and 1
T104 timer 3-phase    277V
Larger image T104 controls 277 Volt
T104 208-240 3-phase    208-240V
Larger image 208-240 volt 3-phase

T-104 timer controls 3-phase

Control 480-277Volt 3-phase : use 277 Volt wiring above or diagram on left
Control 208 Volt 3-phase : Use 240-208 Volt wiring above or diagram on left
Control 240Volt 3-phase : use 240 Volt wiring above or diagram on left

Fused disconnect required on 3-phase line and timer in most commercial applications

How to wire 3-phase timer
480 Volt timer
Larger image

T-104 timer controls 3-phase 480Volt

480Volt timer
Control 480 V 3-phase using T104 timer
Change 240V WG1573 clock motor to WG1576 clock motor

Buy 480 volt clock motor for T100 series:
WG1576 480V at Amazon

Read more about this 3-phase conversion
3-phase contactors
How to wire 3-phase timers

Intermatic clock motor

Change clock motor from 240V WG1573
Install 480V WG1576
WG1576 480V at Amazon
1) Control 120Volt Load using T-104
2) Control 2 - 120 Volt Loads
3) Rewire timer

4) Rewire timer + change clock motor to WG1570 120V

Use this diagram to control 3-phase using T104 timer

T-104 timer controls 120 Volts

Each single phase household circuit takes 2 wires to complete the circuit.

120V takes one 120V hot wire and one neutral wire to complete circuit.

240V takes two 120V hot wires: One 120V hot wire from each busbar to complete circuit.
Read difference between 120 volt and 240 volt

Change clock from 240V WG1573 to 120V WG1570
Buy 120Volt clock motor:
WG1570 for 60 Hz 120V at Amazon

See basic water heater circuit
Intermatic RC939 controls timer  
Larger image            
 RC939 transmitter      RC613 receiver      WH40 or T104 timer

Override timer with remote control

Control 240Volt 3500 watt water heater using Intermatic RC 939 remote control and RC615 120Volt receiver
240Volt circuit can be turned off by turning off 1 hot wire
Do not exceed amp rating of RC615, otherwise install RC613RC relay or PT1203M

RC939 3-channel radio transmitter at Amazon
RC613 receiver at Amazon

Up to 100 feet away
Full product line
RC939 transmitter manual
Remote receiver manual
RC939 3-channel radio transmitter at Amazon

How to find Hot wire

Ground wire not shown.
All ground wires connect to Neutral-ground busbar
Larger image

T-104 timer 240Volt: Pool control center

Control Centers with busbars for installing BR-type push down circuit breakers.

Breakers are installed and wired exactly like main breaker panel

Control centers have T104, T101, T106 mechanisms to control multiple pool functions such as pool pump, pool filter, pool light, outlets, and pool cleaner. Install extra circuit breaker for outdoor lights etc.
Install breakers in control panel

How to wire Intermatic control center breaker busbar
Control center is a subpanel: How to install a subpanel
See inside main breaker panel
How to replace circuit breaker
Intermatic T30000R5
Control center panels:
Sell sheet
Control centers and manuals

Buy bare control center
T21000R Amazon
T30000R Amazon
T40000R Amazon
Wiring for two T104 timers
Larger image
Image for two independent breakers

Two T104 timers for filter and cleaner

Filter pump must be ON so cleaner does not burn up
Both clock motors connect to terminals 1 and 3 on filter timer.
Power only reaches cleaner timer when filter timer is ON


Control centers and manuals
T104 timer with freeze control
Larger image

T-104 timer 240Volts: Freeze thermostat

Prevent pool pump and pipes from freezing
Also use illustration below for SPST

Intermatic freeze controls
PF1112T manual
PF1202T manual
PF1102M freeze control pdf
More control centers and wiring
PF1112T T104 with freeze thermostat
Intermatic freeze control centers and parts
T104 freeze wiring
Larger image SPDT
Larger image SPST
Timer/ freeze control/ and 30 amp switch

T-104 timer 240Volts SPDT :Freeze thermostat

Prevent freezing
178T24 Thermostat overrides timer.
Also use illustration above for SPDT
When temperatures drop toward freezing, the freeze thermostat override timer operation

178T24 thermostat at Amazon
40 amp contactor with 240Volt coil At Amazon

Intermatic freeze controls
178T24 wiring

T-104 timer wired for 480 Volts

WG1576 for 60 Hz 480V at Amazon

Change T104 timer 

by changing clock motor

Intermatic clock motor >>>>> Intermatic clock motor

240 volt clock motor

T-104 timer changed into T104-50

50 Hz timer for use in UK, India etc
WG1574-10D motor 50Hz 208-277V Amazon
T104-50 at Amazon

T-104 timer becomes T103 120 Volts

Change T104 timer into 120 volt timer
WG1570 for 60 Hz 120V at Amazon
Move clock motor wires to terminals A and 1
How to wire T103
How to replace Intermatic clock motor

T-104 timer 24 Volts

CW1570 for 60 Hz 24V at Aplus
Move clock motor wires to terminals A and 1
WG1573 208-277V Amazon

T101 Wiring: How to wire T101 and T171 series timers

Applies to T101, T101R, T101P, T101PCD82, T171, T171R, T171CR, T101R3, T101P3, T101R201, T101P201, T101M, T171M  see all models

T101B Wiring: How to wire T101B timer

Applies to T101B with separate wiring terminals

T103 Wiring: How to wire T103 timer

Applies to T103, T103R, T103P, T103M, T103PCD82, T173, T173R T173M  see all models

How to wire Intermatic T102: How to wire T102 and T172 series timers

How to wire Intermatic T105: How to wire T105 timer

Nema 1 indoor enclosure/
To convert to 208-277V operation, replace WG1570 clock motor with WG1573 clock motor

How to wire Intermatic T106 timer: How to wire T106 timer

Nema 3R indoor-outdoor enclosure
To convert to 120V operation, replace WG1573 clock motor with WG1570 clock motor

How to wire Intermatic pool timer: How to wire pool timers

Additional timers and links

Gas and electric water heaters Industrial electric at Amazon

Industrial supplies at Amazon

Industrial and scientific Amazon
box timers Compare box timers

Compare ways to control Gas and Electric heaters
Intermatic control centers Control centers:
+ manuals and parts

All control centers and parts

Including Z-wave
programmable timer Compare programmable timers

Control water heater with programmable wall timer
Countdown timers Compare countdown timers

Control water heater with countdown timer
Low voltage power packs Low voltage transformers
Yard and Christmas timers Yard and Christmas timers
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