Introduction to Industrial Automation

Figure 2.57  Motorized electromechanical timers from Panasonic Corporation and A.G. 

Engineering Enterprise.

---

68

 

◾

  Introduction to Industrial Automation

Setting disk

Limit

micro-switches

Motor

Gearbox

Dual cam

Micro-switch in

front of the socket

where it is placed

Figure 2.58  Electromechanical switch cam timer-programmer.

Groove

angle

Dual cam

Limit

micro-switches

Motor and

gearbox

Camsaft

Setting disk

Cam timer

housing

10

20

30

330

340

350

Figure 2.59  Details of cam timer programmer components.

---

Hardware Components for Automation and Process Control 

◾

 

69

sequentially energizing and de-energizing various electrical devices. A setting disk, calibrated in 

degrees, facilitates the user to adjust the groove angles and the relative position between them. 

In order to denote the groove angle for each cam with clarity and present the contact status with 

respect to the cycle time, a time bar chart should be designed, such as in the example of a five-cam 

timer shown in Figure 2.60. As mentioned above, the various cam angles correspond to equivalent 

time durations depending on the cycle time. For example, in the case of a 1 min cycle time, the 

groove angles of the first three cams correspond to a time duration of 22.5 s, while the closed status 

of the NO contacts creates an overlapping of 2.5 s with each other.