REMOTE I/O Error 333

[Ronny_resistor 0]

I have two 1747-ASB modules communicating from a 1747-SN placed rack. The modules will operate for about two weeks and then randomily decide to shut down by indicating a 333 fault. I have created my own watchdog timer bit a timed output, that is hard wired to an input on the remote rack. If the output does not return within an amount of time the watchdog indicates a communication failure. The ASB dip switches were set to ignore all faults and to maintain previous on or off conditions. The commanded process is able to run without the SN module communicating. 1774-ASB rack1 SW1- all on, SW2-1 on, SW2-2 on, SW2-3 off, SW2-4 on, SW2-5 on, SW2-6 on, SW2-7 off, SW2-8 on. SW3-1 on, SW3-2 on, SW3-3 off, SW3-4 on, SW3-5 on, SW3-6 off, SW3-7 on, SW3-8 on. My second rack is identical to the previous rack with the exception of SW1-5 it is off (Different address). And SW3-4 off (last Rack). I am communicating to a discrete 32 point input card and a discrete 32 point output card and I am BTR'ing an 8 point Analog input card. I am wondering what would happen if the power supply to the P1 rack power supply is lost ~ 1-2 seconds. Could this cause some issues that could display 333 on the ASB module. Edited 18 Oct 2007 by Ronny_resistor

[OkiePC 14]

Have you tried a replacement ASB? 2nd thought, could you be overloading it with the BTR/BTW set-up in the SLC?

[Ronny_resistor 0]

The attachments are for the Block Transfers PLC file and how the ASB is set up. I figured that a PDF would do better then the RSS file. There is some confusion in my mind with regards to SW3-7 I have been reading up on this dip switch and I am wondering what position this is supposed to be in. It is currently in Discrete since I am using 1/2 slot addressing. The second issue i have come across has to do with Last Chassis, in the Rockwell Manuals (section 8-15) I noted that there can be two last-chassis. This would mean that two remote racks could have dip switch SW3-4 set to last chassis. Does this mean that the both remote chassis have terminating resistors as well ? remote_io_setup.doc RIGID_UPLOAD_10_5_2007.pdf

[Ken Roach 194]

I wish all the posters on these Forums included as much information. Good work. The "Last Chassis" function is best described on page 4-19 of the 1747-UM006 User Manual for the 1747-ASB: A 1747-ASB module should be configured as the last chassis when: • Its image crosses logical rack boundaries and no other adapter uses a higher group number within its last logical rack. • It uses a portion of a logical rack and no other adapter uses a higher group number within that logical rack. Both of the chassis you've configured meet the second criteron, so you would set them both as "last chassis". "Last Chassis" has nothing to do with Rack Numbers, or with Terminating Resistors. It only refers to whether or not there is another adapter using a higher Group Number in the same "Logical Rack". In my experience it only really makes a difference with PLC-2 scanners.

[Ken Roach 194]

Error 333 is a "watchdog reset detected" error, and appears to be related to power or noise or actual component failure. First check the power supply jumper on that 1747-P1. It comes from the factory set for 240V. Make sure you have the cable terminated only at the two extreme ends of the RIO daisy-chain, and make sure it's not routed near any higher voltage cables.

[Ronny_resistor 0]

Ken I have been working with R-I/O for about 12 years. This is the first time I have had this type of problem. The only difference is that the first Remote 4 slot rack is about 150 feet away and the second rack is about 300 feet away. My usual installation of the remote rack(s) is about 40 feet away. I am wondering if the P1 power supply is large enough to maintain the ASB communication. The Remote I/O Blue hose is in a metal conduit running the length of the machine. The reason why I have stood behind R-i/o is because it is idiot proof (dip switches). With the Hold last state you can ride through mis-communications (provided you can safely) If you look at the re-try counters in my program you can see that I am missing some of the data packets (missing perhaps 10 per 1000). Just missing some of the communications should not bother a watchdog, should it ? During commissioning I removed the R-I/O blue hose and noted that there was a mesage displayed and a sequence of flashing LED's but when the Hose was re-inserted the unit continued as if it was never removed. The 333 message basically wants me to cycle the power for a re-start. I am also wondering about the block transfer set-up. My ASB dip switches are set to Discrete transfer, the manual wasn't to clear about SW3-7 (Block transfer/discrete mode). The un-clear part is composition of the remote rack: (1) 1746-IB32 and (1) 1746-OB32 and (1) 1746-NI8, If the rack was comprised without the NI8 then I would assume discrete, If the rack was comprised of NI8's then I suppose the dip switch must be in Block Transfers, what the manual doesn't state is what if you have a combined input cards do you set DIP SW3-7 in Block Transfer mode ??? By using a discrete setting would that cause numerous errors to occur in the BTR's (In my program there are error counters just past the BTR instructions that are limited to 5K before resetting) or are BTR error's a natural event ??? I have attached my schematics as well as a remote addressing scheme (keep in mind the addressing was based on the ability to expand the rack sizes). Sincerly Rick rack1.pdf rack2.pdf RIO.pdf