Different types of Relay

[UKB]

I'm struggling to find any descriptions of the different functions provided by these various relays in the mitsubishi documentation (surprise surprise)

Can anyone offer me some definitions, are these typically the same across the PLC board?

Where might I use a step relay instead of an annunciator relay etc..
Are there such things as annunciators and step relays in AB, Siemens, GE,
etc..?

Whats a link register when compared to a data register? or even link special?

Kind Regards,
UKB.

 

[dlweber]

http://www.plctalk.net/qanda/archive/index.php/t-67931.html

Google =)

 

[Lancie1]

Where might I use a step relay instead of an annunciator relay etc..
Are there such things as annunciators and step relays in AB, Siemens, GE,
etc..?

Step relays are special-purpose relays that are designed for dividing a program into incremental steps, so that each set of rungs or networks is only active when the step relay assigned to that step is active or energized. Annunciator relays are used to send alarm or other or messages to the operator or HMI panel.

The following PLC devices (really instructions being run by the Central Processing Unit in the PLC) function more or less the same from PLC brand to brand, with minor variations (such as different symbols and addresses):
Output Relay
Internal Relay
Latch Relay
Edge Relay
Step Relay
Timer
Retentive Timer
Counter
Data Register

The other items on your list may be missing completely, or implemented very differently in different brands and models.

 

[UKB]

thanks guys,
I'm interested in the step relay as I have constructed most of my ladder as a sequencer, which sounds very similar to the step function.
I will make a more detailed post when I'm at home later,

this is a scrn dump of the manual, a nicely constructed list unfortunately for greenhorns (me) there doesn't appear to be any further explanation as to the nature of the devices

 

[osmanmom]

other type of relay

 

[Ronnie Sullivan]

And another type of relay

Oh wait................that's real hay

 

[Tom Jenkins]

Mitsubishi used to have a manual with descriptions and examples of each command. I suggest you contact your vendor for assistance.

(And most bales nowadays are round, Ronnie!)

 

[dploof23]

Which type of Mitsubishi PLC are you using?