GM40 timer
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How to wire GM40    GM40AV    GM40AVE   WHQ series
DPDT timers/ all with indoor-outdoor Nema 3R enclosure
Applies to Intermatic, GE, Tork, Woods
GM40 timer
Larger image
Permanent ON-OFF override
GM40 Intermatic WQ timer
40 amp  120V-208V-240V-277V
Dip switches to select voltage
7-day with 15 minute intervals or 24 hour with 1.75 hour intervals
Buy
Buy GM40 24 hour at Amazon
Buy GM40 7-day at Amazon
Buy:
WHQ4     120-208-240-277Volt 24-hour at Amazon
Resources
GM40 instruction manual
Sell sheet with model numbers
How to set analog timers
Intermatic timers and manuals
GM40 timer
Permanent ON-OFF override
 GM40AV
40 amp 120V-208V-240V-277V
Automatically detects voltage
24 hour, 15 minute intervals
Power outage backup option
Buy:
GM40AV       120-208-240-277V at Amazon
GM40AVQ       w/ back-up battery at Amazon

Manuals/ Resource:
GM40AV Manual
GM40AV sell sheet
Intermatic GM40AVE
Larger image
Permanent ON-OFF override
GM40AVE digital
40 amp 120V-208V-240V-277V
Automatically detects voltage
7-day programmable, 20 on 20 off set points
Power outage backup
Buy:
GM40AVE  120-208-240-277Volt at Amazon
GM40AVE at Intermatic

Manuals/Resources:
GM40AVE manual
GM40AVE sell sheet
FM1D 20 setpoint programming
FM2D 50 setpoint programming
Intermatic timers and manuals
woods wion contactor Woods Wifi
30 amp Woods 50054 WiFi contactor
Auto detect voltage/ 120, 208, 240, 277 volt
WiOn contactor connects to app on phone
How to wire wifi
Buy
WiOn contactor from Amazon

Resource:
How to wire WiOn for 120 volt and 240 volt
Woods 59402 timer
Larger image
Permanent ON-OFF override
Woods 59402
40 amp 120V-208V-240V-277V
Select voltage using jumpers
24 hour, 15 minute intervals
Buy:
Woods 59402 timer at Amazon

Manuals/ resources
Woods 59401 and 59402 manual
Woods timers and manuals

GE 15136 timer
GE timers and manuals
GE 15135
40 amp 120V-208V-240V-277V
Dip switches to select voltage
24 hour, 15 minute intervals
Buy:
GE 15135 24-hour/ 40 amp/ outdoor metal box at Amazon
56922 at Amazon

Manuals/ Resources:
GE 15207 manual
How to wire GE indoor 15207
GE 15136 timer
GE timers and manuals
GE 15136 digital
40 amp 120V-208V-240V-277V
Dip switches to select voltage
7-day programmable, 9 on 9 off set points, with countdown and random options
3 month power outage back-up
Buy:
GE 15136/ 7 day/ 7 programs /40 amp/ outdoor metal box

Resources:
GE 15132 manual
How to wire GE 15136
Tork TU universal timer
Larger image
Permanent ON-OFF override
Tork TU series
40 amp 120V-208V-240V-277V
Automatically detects voltage
24 hour 15 minute intervals
Buy:
Tork TU series DPDT/ 120-277V universal timer at Amazon
Tork P1104-M 240Volt SPDT at Amazon
Tork P1104FM 240V SPDT with fireman switch at Amazon
Buy Tork DTU digital timer at Amazon

Manuals/ Resources:
Sell Sheet
TU wiring manual
TU instruction manual
Tork DTU water heater timer
Larger image
Permanent ON-OFF override
Tork DTU digital
40 amp  120V-208V-240V-277V
Automatically detects voltage
Replaces Intermatic GM40E
7-day programmable, 7 on 7 off set points, with random option.
Power outage back-up
Buy:
DTU40 At Amazon

Manuals/ resources
DTU40 instruction manual
GM40 timer 240 Volt and 208 volt
Wire GM40 for 240Volt water heater

Basic 240Volt wiring
Turns OFF both hot wires going to load

Resource
More ways to wire for 240Volt
Figure volts amps watts for water heater
Wire size charts

When black-and-white wires are used for 240Volt, add black tape to white wire.
This practice will notify any electrician that white wire carries power.
GM 40 timer controls 2 water heaters 240 volt and 208 volt
GM40 controls two 4500 watt 240Volt water heaters
Turns off 1 hot wire to each water heater

Use 50 amp breaker and 6 gauge wire to timer.
10 gauge ire to each water heater
Timer not rated for controlling two 5500 watt water heaters

Resource
How water heaters work
How to wire water heaters
Figure volts amps watts for water heater
Two water heaters
Wire sizes
240 volt and 208 volt
GM40 controls two 4500 watt 240Volt water heaters using dry terminals
Set dip switches for 240Volt
Timer can control two different voltages, and two separate circuits.
Both circuits turn ON-OFF at same time.
Control any voltage with dry terminals that are separate from clock terminals
Two separate wires from breaker box.
Turns off 1 hot wire to each water heater

Use two 30 amp breakers and 10 gauge wires when wiring two 240Volt water heaters with element wattage over 3800 watts.

GM 40 timer controls two water heater
240 volt and 208 volt
GM40 controls two 240Volt water heaters

One or other water heater is ON.
Both heaters not ON at same time
Use 10 gauge wire


Resource
Two water heaters


GM40 208-240 controls 3-phase
Larger image
120-208-240 volt 3-phase
Example: High leg delta
GM40 3-phase timer 120 or 208 or 240Volt
3-phase line and timer must have fused disconnect
Resource
See more 3-phase
What is 3-phase

High leg delta
Timer toggle between 240 volt loads
Larger image
Toggle between 30 amp Loads
Sometimes there are not enough circuit breakers for  new 240 volt 3 HP irrigation motor.
Use timer to toggle between 240 volt loads, and set timer to schedule irrigation pump. When pump is off, the water heater receives power.

240Volt circuit can be cut off by turning off one hot wire.
Put water heater on NC normally open terminal, so water heater is ON when pump is Off.

Same can be accomplished using 30 amp 3-way switch
Buy:
Leviton 3033-2 3-way switch at Amazon
Leviton 3-way 30 amp switch
Pass and Seymour 30 amp 3-way switch

Dishwashers at Amazon

Resource
How to wire 240Volt outlets
Motor resources
Not enough circuit breakers
GM timer controls 2-speed pump
Always check pump voltage and wiring diagram located on nameplate
Pump operates continuously. Install another timer on L2 Hot line to turn pump ON-OFF
240 volt or 208 volt 2-speed pump

Low speed is connected to NC terminal, and then pump operates continuously in low speed until timer turns ON.
When timer turns ON, High speed turns ON.
Diagram applies for both 120V and 240V 2-speed pool pumps.

Other timers can be used for 2-speed pool pump:
Resource
T106 timer
T1906 timer

Change water heater temperature using timer
Larger image
Change water heater temperature using GM40 timer
Applies to all DPDT timers shown at top of this page
Also applies to SPDT Intermatic T106 timer
240 or 208 Volt electric water heaters Intermatic GM series
Use timer for two different temperatures on electric water heater.
This plan allows normal 120F temperature for saving energy, and then increase temperature to 130-140F for sterilized wash day or certain times of day. The same can also be accomplished with DPDT 40 amp switch or relay.
140F is extremely dangerous. Typical bath shower is 110F and Hot tub 105F

Operation plan has two states: Either upper thermostat and element have power -or- lower thermostat and element have power. But not both at same time.
When timer activates, power to lower part of tank turns OFF. Power to upper part of tank begins. Upper thermostat is set for higher temperature resulting in very hot water at top of tank, but not whole tank. Disadvantage: If the upper part of tank is heating, then lower part of tank is off, so lower part of tank will cool rapidly as new cold water enters tank, therefore this technique is good for making short-term batches of very hot water.

Work required: Install ECO-protected thermostat for lower thermostat. This ensures both upper and lower parts of tank are ECO-protected from overheating.
Rewire tank so upper and lower parts are separate. Add 2 extra wires.
Use GM40 timer to toggle power between lower and upper parts of tank.

Other options include: 2 water heaters, mixing valve, recirculation system
Resourcese
How to wire thermostats
How to replace thermostats
Two water heaters
Advantages mixing valve
Recirculation system
Add another thermostat to gas or electric water heater
How electric water heaters work
How to wire off Peak water heater
GM40 timer wired for 277 volts 277 volt
Timers with automatic voltage detection do not have dip switches, and will detect 277 volt.
GM 40: Set dip switches for 277Volt.
Dip switches must be set before power is applied to timer


Wiring is identical to 120Volt, with Hot and Neutral.
277 volt is a derative of some commercial 3-phase 440 volt services, and does not apply to residential 120-240 volt services.

Resource
How to wire 3-phase timer
What is 277 volt
Wire GM40 for two 277Volt loads 277 volt

Wire GM40 for two 277Volt loads
Both loads turn ON-OFF at same time
Do not exceed timer 40 amp rating
Volts x Amps = Watts.
Each electrical device has rating plate

Resource
Wire and breaker size charts
GM40 277Volt 3-phase
Larger image
277 volt 3-phase

Wire GM40 controls 3-phase
Use 277V
Or 480V contactor

Fused fused safety switch, or disconnect, is required on 3-phase line and timer in typical installation.

277-480 3-phase
Resource
How to wire 3-phase timer
See more 3-phase
How to wire fused safety switch
GM40 timer 120 volt

Wire GM 40 for 120Volt water heater

Set dip switches for 120Volt.
Dip switches must be set before power is applied to timer

GM40 120 volt 120 volt 2 loads
Both loads turn ON-OFF at same time
Do not exceed timer 40 amp rating
Volts x Amps = Watts.
Each electrical device has rating plate
3 phase timer
Larger image
120 volt 3-phase
Use GM40 to control 3-phase circuit
Most buildings with 3-phase also have 120Volt outlets.
Use 120volt to power timer. Wire timer as shown in illustration directly above.
Timer opens-closes circuit to 3-pole contactor with 120Volt coil.

Resource
See more 3-phase

GM 40 timer is NOT rated for DC voltage, but can switch 24 DC volt line
Wire GM40 timer to control DC motor:
Use same diagram to control any single-phase voltage.
Buy:
Omron-DC-Power-Relay
Resource:
DC relays
Do not mix different gauge wires under same screws. Smaller wire comes loose, causing sparking and high heat and fire.
Do not mix solid wire and stranded wire under same screw.
Intermatic terminal wires
Toggle between 120 volt or 240 Volt
Off Peak Wire GM40 timer to toggle water heater between 120Volt and 240Volt.
Wiring inside water heater is not changed
Elements and thermostats will work with 120 or 240
This will not work for Whirlpool energy smart water heater, electronic water heaters, heat pumps, tankless, etc

Use this technique for peak electric prices.
When prices are peak, set water heater to operate at 120 volts for slower heating. Tank stays hot, but hot water does not recover quickly.
Element rated for 4500 watts @ 240Volt, will consume 25% or 1125 watts @ 120Volt and heat water 1/4th as fast as 240 volt.
When peak price ends, resume 240Volt operation for faster heat recovery inside tank.

Resource
Off-peak water heater options
cycle timer Turn Load ON once every 10 minutes for 8 hours per day

Set 120Volt cycle timer for chosen time duration. For example once per each 10 minutes. Or once each 5 seconds. The cycle timer dial rotates continually, and turns load ON-OFF for each cycle.

To operate the cycle timer at different hours, install GM40 timer.
GM40 timer can be installed on the Hot line before or after the cycle timer.

Resource
Read more
CT2000 cycle timer

Intermatic IG1240RC3
Whole house surge
Larger image
Surge
Resource
Whole house surge protector
How to wire whole house surge protector

Digital timers should be protected from surge.
Same with any water heater that is plugged into outlet.
All new appliances and water heaters with digital controls are vulnerable to surge
Control 2 water heaters
Larger image
Control 2 water heaters using 2 EH40 timers

Each water heater can have different 7-day schedule

10 gauge wire and 30 amp breaker run cooler.
30 amp circuit breaker and 10 gauge wire for water heater runs cooler with less energy loss. Breaker box lasts longer.

Different wiring:
For two 4500 watt water heaters, you can use one 40 amp breaker and 8 gauge wire to bring power from breaker box to the first timer.

For two 5500 watt water heaters, you can use 50 amp breaker and 6 gauge wire

Resource
Water heater timers
EH40 water heater timer
Things you can do to increase amount of hot water

9 ways to save with water heater
Support the economy:
Buy water heaters from my associate links:

50 gallon Gas water heaters at Amazon
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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
Install and troubleshoot garbage disposal Waste King disposal
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Anode rods anode rods
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Tankless recirculation
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