I won an auction for two pre-used units for a low price(<5% of the new price). They are PID controllers with ramp, soak, profile and RS485
interface.
They are very nice controllers with lots of programmable function with various inputs and outputs. But they are a nightmare to program with its five
front panel buttons, a seven segment display and 78 pages of options, way to many complicated options for my old brain to manage easily.
Watlow does provide free PC software to program them that does looks much simpler to use but I am struggling to get the software to interface to them
via a cheap usb to RS485 convertor.
For now I am giving up as I don't need all the bells and whistles at the moment. I will use one of those cheap REX-C100 controller that is much
simpler to program. Its only for a small hot plate.
wg48temp9 - 25-5-2022 at 09:16
Before I gave up on the fancy controller I decided to try one more time to get the RS485 interface and PC software working.
I am very happy I got it going. I probably had the RS485 incorrectly set up.
The PC software is simple to use. Unfortunately my version of the controller does not have a profile function and only one ramp function.
I also need logging function. Watlow does have software to do that but I would have to purchase it.Organikum - 24-7-2022 at 01:51
Thats a nice controller. The interface should be industry standard and interface with most logging software, there are a few free ones out there IIRC,
or it might be possible to locate an unrestricted evaluation copy of the Watlow software?
Damn, the early REX C-100 knockoffs from China had all the bells and jingles for 5 bucks (not mentioned in the manual but it was all there) except the
RS485 module, and now they got so bad and some have not even an alarm left.
OpenHab the open source house control software might have the needed connectivity, I believe there is a module for RS485 and as it is designed to be
able to connect everything and its cow there is a good chance that it interfaces to the Watlow too. Logging function is understood, profile should be
possible too. Maybe worth a look.Rainwater - 24-7-2022 at 03:54
If you have the Modbus point map, it would be easy to put an rs485 shield onto an Arduino, pi, or your existing computer and implement a profile otw.
Code:
1) send first setpoint, start timer or event trigger
2) send second setpoint. Reset timmer or trigger
... repeat
Data logging would be just as easywg48temp9 - 24-7-2022 at 13:21
Thanks Organilkum and Rainwater for those suggestions.
Using a usb sniffer I examined the communications between the Watlow PC software and the controller. I was hoping to understand the protocol so I
could emulate it with an arduino. It was way more complicated than I expected. When changing just one parameter i could not figure which word
corresponded to the new parameter. I suspect that there was a lot of chat just to get the communication going.
The controller does have a Modbus which is accessible via the serial interface but without knowing the procol I am lost.
Its particularly irritating because I have mass flow controllers, vacuum gauges and a compressed air solenoid unit that all have the RS485
interface. Rainwater - 24-7-2022 at 14:12
Analyzing data streams can be a real pain in the ... lower back. May I suggest storing your entire data dump into a raw file and then letting https://www.winpcap.org/ tell you what it is saying. With over 4000 standardized protocols and the industries most advanced ai analytics it can
decipher most protocols in just a few cycles of the CPU. It's open-source software from the same people who brought you tcp/ip, inds, dsl and 4Glte. I
usually use it to translate wifi to see where im messing up my handshakes and to spy on the negiborhood but it does spi, i2c and much much more. All
for the low low price of free.
All bs aside. I use it at work to troubleshot modbus and bacnet. You don't need any additional packages or patches works straight out of the box.
Edit:
Please verify this manual is for your specific piece of equipment.
If so review page 42 and page 104 for address points, data sizes, item meanings.
Attachment: pm pid 1.pdf (6.7MB) This file has been downloaded 514 times
Edit: holy crap this is a bad !@@ ?[/&รท= $<"(>,% controller. Now i want one
[Edited on 24-7-2022 by Rainwater]
[Edited on 24-7-2022 by Rainwater]wg48temp9 - 24-7-2022 at 17:03
Rainwater:
Yes that's the manual for it. The part number is PM6C2FA-AREADAA which defines the particular options it has. Its got the standard bus EIA-485
option.
A read page 42 again but it did not help. I probable need to read it several time more.
winpcap is interesting but its probably beyond my knowledge to use it.
edit:Apparently i already have winpcap, Ouch! its complicated.
