PLC 5/25 Allen-Bradley

S

Thread Starter

Salman

I have a PLC5/25 connected with 1771-ASB ser B module on Remote I/O port. I am unable to communicate with PLC 5/25 and 1771-ASB module. Both LEDs Active and Fault are blinking at once on 1771-ASB module (it indicates that u should check DIP switch setting). I have connected my PC to PLC 5/25 by 1784-KTX card through DH+ link on programming port (3 pin DH+ port).

Regarding DIP switches I have the following questions:

1- SW1 switch8= should be set on Adapter (ON) or scanner (OFF). When Adapter mode is selected and when scanner mode is selected, should I use Adapter mode or scanner mode for communicating b/w 1771-AB and PLC5/25?

2- On my Processor (5/25) it is given that on
SW2 switch 1 = OFF (for 57.6Kbs baud rate),
in manual it is given an unused bit.

3- Should I close SW3 swtich 1 =ON (end of Remote I/O node?
Shoud I close SW3 switch 2= ON (End of DH+ node?

4- Remember I am using 1/2 slot addressing with 32 bits modules. I have 16 slots in my local chassis. So my PLC chassis will occupy rack 0, rack 1, rack 2 and rack 3.

5- So what address do I put on rack number in SW2 (switch 4-8)?
What address do I put on 1771-ASB SW1 (switch 1-6)?

6- What should I select on SW2 switch 2 (half or full) PLC 5/25 processor?

With regards,
M.Salman
 
B

Bradley Hite

Hello M.Salman,

> I have a PLC5/25 connected with 1771-ASB ser B module on Remote I/O
> port. I am unable to communicate with PLC 5/25 and 1771-ASB module.
> Both LEDs Active and Fault are blinking at once on 1771-ASB module (it
> indicates that u should check DIP switch setting). I have connected my
> PC to PLC 5/25 by 1784-KTX card through DH+ link on programming port
(3
> pin DH+ port). <

You really should be plugging the KTX card into the DH+ programmer port on the front of the processor. The DH+ programmer port is the 9-pin port on the front of the processor. However, it does not hurt anything to plug into the 3-pin network port.

> Regarding DIP switches I have the following questions:
> 1- SW1 switch8= should be set on Adapter (ON) or scanner (OFF). When
> Adapter mode is selected and when scanner mode is selected, should I
> use Adapter mode or scanner mode for communicating b/w 1771-AB and
> PLC5/25? <

Dip Switch 8 on the top of the processor should be set for scanner mode (OFF position).

> 2- On my Processor (5/25) it is given that on
> SW2 switch 1 = OFF (for 57.6Kbs baud rate),
> in manual it is given an unused bit. <

Dip Switch Bank S2 on the bottom of the processor, switch 1 should be OFF.

> 3- Should I close SW3 swtich 1 =ON (end of Remote I/O node?
> Shoud I close SW3 switch 2= ON (End of DH+ node? <

Dip Switch Bank S1 on the bottom of the processor
Switch 1 should be ON if the processor is at one end of the DH+ network and you are not using an external terminating resistor. If the processor is not at one of the ends of the DH+ network or if you are using external terminating resistors then this dip switch should be OFF.

Switch 2 should be ON if the processor is at one end of the RIO network and you are not using an external terminating resistor. If the processor is not at one of the ends of the RIO network or if you are using external terminating resistors then this dip switch should be OFF.

> 4- Remember I am using 1/2 slot addressing with 32 bits modules. I
have
> 16 slots in my local chassis. So my PLC chassis will occupy rack 0,
> rack 1, rack 2 and rack 3. <

How do you have the 32 point cards arranged in this chassis? If they are alternating then you do not have to use 1/2 slot addressing.

> 5- So what address do I put on rack number in SW2 (switch 4-8)? <

Nothing. Those dip switches are not used when the processor is configured for scanner mode.

> What address do I put on 1771-ASB SW1 (switch 1-6)? <

I would suggest setting the ASB adapter as Rack 04. ASB module Dip Switch Block S1 Dip switches 1,2,3=OFF position, Dip Switch 4=ON position, Dip Switches 5,6=OFF position, Dip Switch 7,8=ON Position. These settings configure the ASB adapter for starting Rack number 04 and starting group number 00.

> 6- What should I select on SW2 switch 2 (half or full) PLC 5/25
> processor? <

Dip Switch Block S2 on the ASB adapter. Dip Switch 1=ON, Dip Switch 2=OFF, Dip Switches 4,5,6=OFF. These settings configure the ASB adapter for 57.6kbps comm. Speed.

If the ASB module is the end device on the RIO network then it must have a 150 Ohm terminating resistor placed between the two (2) signal conductors of the "Blue Hose" cable on the terminal arm of the ASB module.

Bradley G. Hite
Intertech Inc.
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