4

Programming a Normally-Open Contact in Series

When a Normally-Open contact is not the first element of the rung, program an AND with the HHP, as shown below. The example shows how to use the HHP to program a Normally-Open contact at the first and second positions in a rung.

46115

Ladder Diagram

I1

I2

 

O17

 

 

 

 

 

 

 

 

 

 

Hand-held Programmer

START

I1

AND

I2

OUT

O17

Timing Diagram

Input I1

Input I2

Output O17

AND operation of inputs I1 and I2; output O17 is 1 when I1 and I2 are both 1.

Programming a Normally-Open Contact in Parallel

To enter a Normally-Open contact in parallel, as shown by I2 in the following example, program an OR with the HHP.

46116

Ladder Diagram

I1O17

I2

Timing Diagram

Input I1

Input I2

 

Hand-held Programmer

START

I1

OR

I2

OUT

O17

OR operation of inputs I1 and I2. The output O17 is 1 when either I1 or I2 is 1.

Output O17

4-6

Micro PLC Programmer's Guide ± April 1994

GFK-0804B

Page 47
Image 47
GE GFK-0804B manual Programming a Normally-Open Contact in Series, Programming a Normally-Open Contact in Parallel