Intermatic T103: Can it be Used for One Device & Wiring Question

[Shuriko]

Last weekend my brother purchased an Intermatic timer at a garage sale because he knew I was looking for something like that to turn on and off my exterior garage lights. He wasn't sure of the model and took a chance for $6.

What I originally thought was a model T101 it turned out to be a model T103. The difference between the two is that the T101 is a SPST switch and the T103 is a DPST switch.

Can I use the T103 timer to simply turn on/off my 3 exterior lights (at the same time) if it is only a single load into the timer? The SPST switch is easy for me to understand but I want to make sure the DPST isn't going to be a problem. Also I may in the future configure the timer to go on and off multiple times in a 24 hour period.

The 2nd question is, if it can be used for this purpose, why isn't there a screw for the neutral wire coming off the load (see attached instructions)?

I compared the T101 instructions and it clearly shows the neutral wire for the load but the T103 instruction only shows the hot & ground sides of the load.

Thank you

 

[ishiboo]

Last weekend my brother purchased an Intermatic timer at a garage sale because he knew I was looking for something like that to turn on and off my exterior garage lights. He wasn't sure of the model and took a chance for $6.

What I originally thought was a model T101 it turned out to be a model T103. The difference between the two is that the T101 is a SPST switch and the T103 is a DPST switch.

Can I use the T103 timer to simply turn on/off my 3 exterior lights (at the same time) if it is only a single load into the timer? The SPST switch is easy for me to understand but I want to make sure the DPST isn't going to be a problem. Also I may in the future configure the timer to go on and off multiple times in a 24 hour period.

The 2nd question is, if it can be used for this purpose, why isn't there a screw for the neutral wire coming off the load (see attached instructions)?

I compared the T101 instructions and it clearly shows the neutral wire for the load but the T103 instruction only shows the hot & ground sides of the load.

Thank you

1. Yes, you can. You simply do not use one of the sets of "line" terminals.

2. The 103 is designed for 240v circuits, the neutral is only present on the timer to run the clock motor. You can pigtail the neutral so it attaches to both the timer and goes out to the load. The clock motor operates off 120v on both timers.

 

[Shuriko]

1. Yes, you can. You simply do not use one of the sets of "line" terminals.

2. The 103 is designed for 240v circuits, the neutral is only present on the timer to run the clock motor. You can pigtail the neutral so it attaches to both the timer and goes out to the load. The clock motor operates off 120v on both timers.

Thanks ishiboo.

I was under the impression that the T101 and T103 were both designed for the same 120v circuits. If the T103 is designed for 240v circuits can I still use to power up CFL bulb lights?

 

[Norcal]

Thanks ishiboo.

I was under the impression that the T101 and T103 were both designed for the same 120v circuits. If the T103 is designed for 240v circuits can I still use to power up CFL bulb lights?

No problems, it's just your basic mechanical time switch. Check the voltage of the timer motor, Intermatic has 2 models, 1) 125V, 2) 208-277V. they are easy to replace if required.

 

[Shuriko]

Thanks Norcal.

The instructions indicate that the motor operates at 125v.

As I studied the T103 instructions more carefully I think I better understand ishiboo's comment with regards to the 240v comment. The timer allows for the 240v source to split into two 120v circuits thus each leg may control separate loads using the DPST swtich capability. Well I think that is what the diagram is conveying.

 

[huifenghe73737]

The instructions indicate that the motor operates at 125v.

 

[winnipegk5]

The T101 is for one circuit. The T103 is for two. Basically you can switch two full seperate 120 volt loads with this clock or one 240 load. They will switch both on and off at the same times though.