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  4. REC Master9M with new REC2Q Slave Units - Cable from Master to 1st Slave: which cable colour goes where

REC Master9M with new REC2Q Slave Units - Cable from Master to 1st Slave: which cable colour goes where

  • M

    A few weeks ago I received 1 REC Master 9M and 3 of the new REC2Q Slave units for a 12V 3 parallel bank installation directly from REC in Slovenia.

    They also included the RS485 cable from the Master9M to the 1st REC2Q slave.

    This cable has the female DB9-Sub plug on one end and 6 differently coloured cables with the pins already crimped to insert these pins at the RS485 in on the 1st slave at the pins 4,5,6,12,13,14 on the TE Connectivity 14pole plug (TE 749202-1).

     

    My problem is: No matter how often I read the available manuals (I know they are in revision due to the new REC2Q's) I can't find out which pin on the Master9M DB9-Sub carries which cable (RS485 Signal A, RS485 Signal B, GND, Shield, +5V and +5V BMS enable from Master).

    Anyhow I found out by measuring conductivity which pin on the DB9-Sub female goes to which cable colour:

    Pin 1: Black cable

    Pin 2: Gray cable

    Pin 3: Green cable

    Pin 4: Yellow cable

    Pin 5: not used

    Pin 6: Pink cable

    Pin 7: not used

    Pin 8: not used

    Pin 9: White cable

     

    But this doesn't help me as I still don't know the pinout on the Master9M DB9-Sub male.

    I already wrote Tine at REC directly and he sent me a reply. He wrote:

    "RS485 Communication:

    Master-Slave communication

    Master:

    DB9 Slave

    1 shield

    2 GND RS485

    3 B

    4 A

    6 RS485 5V power "

     

    So this are only 5 cables or pinouts but I have 6 cables on the other side.

    I'm interpreting this as if the white cable on pin 9 was missing in his pinout and this must be the cable for +5V BMS enable by Master in a Master-Slave configuration.

    Can anybody here confirm that my following assumption is right ?

    Maybe this will help also all other users who have the new Master-Slave combo....

    Assumption:

    Pin 1: Black cable = Shield

    Pin 2: Gray cable = GND

    Pin 3: Green cable = RS485 Signal B

    Pin 4: Yellow cable = RS485 Signal A

    Pin 6: Pink cable = +5V RS485

    Pin 9: White cable = +5V enable REC2Q Slave from Master

     

    Do you think my assumptions are correct ?

    Thank you everyone for your your help.

    Kind regards.

     

    Martin

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  • R

    We did this sketch a while back for our customers.  Hope it helps

    REC BMS Master-Slave Pinout

     

     

  • P

    I'm in the process of working on this same wiring for one 9M master and two 2Q slaves. 

    While I did purchase the necessary cables, I still will need to insert the wire terminals into the 14-pin MNL housing. So the right half of that diagram is very helpful.

    That diagram above, which is also on page 4 of the document "REC-Series-Master-2Q-Slaves-Wiring-1-0-1.pdf", has an error in the pin numbering for the DB9 connector. Pins 6-9 are reversed; pin 6 should be at the bottom and pin 9 at the top, in the view shown. That view, BTW, is shown as looking at the mating face of the socket-pin plug, not the soldering side of it. Luckily, most DB9 connectors included numerals molded into the plastic insert!

  • P

    FWIW, the later revision of the wiring diagram document, "REC-Series-Master-2Q-Slaves-Wiring-1-0-1-6.pdf" still has the pin numbering error on page 4 at the DB9 connector.

    Again, pin 6 is at the bottom (Pink +5v Out) and pin 9 is at the top (White +5V In).

    So the physical positions of the White and Pink wires are shown correctly; it's just the numbering (6, 7, 8, 9) that is backwards (should be 9, 8, 7, 6 from top to bottom).

  • Rob

    @PeterD ....  I am in the middle of the same problem. Master & 2 slaves.

    Could use some serious help

    Solar@robtribble.com 

    Rob tribble

  • Rob

    @PeterD ... so looking at the plug from outside which pin gets what color.

    Big trouble here need help

    Solar@robtribble.com 

    Rob tribble

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  • R

    Just updated DB9 pin numbers and added a Slave to slave pinout section to the Master Slave Pinouts diagram.  Thanks to PeterD for catching it.  You can download it here:

    https://rec-bms-na.com/download/39/rec-master-slave-bms-sketches/1576/rec-master-slave-network-pinout.pdf

  • Rob

    @Rick will check it out

    Rob tribble

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  • P

    Hi Rick and Rob,

    With all due respect, Rick, I believe you have the two "+5V" lines mixed up. Looking at the product manual from REC, the pins are all clearly described, and I have verified the wire colors to be as shown in the attached marked-up diagram. In the 14-pin connector, #5 is the Enable, and #14 is the +5V power. In the 6-pin connector, #3 is the Enable, and #4 is the +5V power. Most likely the confusion stems from the fact that REC uses "+5V" within the description of both signals. But clearly one is has the "enable" function, while the other is supplying power. As well, in the cables I received, at the 14-pin end, #5 has the white wire and #14 has the pink wire. Finally, the shield was black in my cable, so may be either brown or black.

    Diagram

  • Rob

    @PeterD so guys what is correct ?

    Rob tribble

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  • P

    Martin, in his original posting above, correctly identified the wire colors and meanings connected to the DB9:

    Pin 1: Black cable = Shield

    Pin 2: Gray cable = GND

    Pin 3: Green cable = RS485 Signal B

    Pin 4: Yellow cable = RS485 Signal A

    Pin 6: Pink cable = +5V RS485

    Pin 9: White cable = +5V enable REC2Q Slave from Master

    And Rick's original diagram, also seen above, was correct as far as which color goes to which pin on the 14-pin MNL (mate-n-lock). The only error in his diagram, as I pointed out several months ago, was the numbering shown for the DB9. The positioning of the wire colors was correct. 

    Rob, can you describe what problem you are having? Or are you just wanting to be certain before connecting things?

    HTH

  • Rob

    @PeterD the #2 slave would not communicate with master.

    #2 as a standalone was working fine.

    Then I was instructed to download the slave firmware to #2.

    I moved the wifi back to #2, and did so, then #2 quit working at all. The one red light blinked on start, but contactor did not engage.

    Then I tried wifi nothing on #2. Move wifi back to master. And wifi won't work there either. Tried reset an nothing on wifi. No lights at all. I test power and it was 53vdc, but no lights on wifi

    Rob tribble

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  • Rob

    @Rob please be very specific about pin, colors on 14 end and 6 end on master/slave cable and what the correct diagram pdf is correct

    I believe that is where my problem is since bms#2 will not activate.

    Rob tribble

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  • P

    @Rob Just to be clear, while I am certain about what I am showing in the Diagram PDF that I uploaded 17 hours ago, OGM Energy, represented by Rick, must be the final arbiter. After all, they are your official source for support of this product.

    That said, I will try to help by going through some basic troubleshooting steps:

    1. If you connect the WiFi module (hereinafter "WFM") to the Master, disconnect both slaves from the RS-485 DB9 connection of that Master, and power up just the Master and then the WFM, can you communicate with the Master at all via the WFM?
    2. If that works, though the Master may be throwing errors because the slaves are absent, then the next thing to try is powering each slave by itself, with the WFM connected to the correct RS485 connector on the slave, and with a terminator plugged into the 6-pin on that slave.
    3. Be sure that every time you are making/breaking any connections, that you are following the correct sequence as desribed in the 2Q manual!
    4. If the WFM allows communication with each slave, even though again they will be throwing an error possibly, then you are ready to connect both slaves to the Master, daisy-chained, via RS485.
    5. Note that when a slave has the correct "slave firmware" installed, when you turn on its power, the light blinks quickly but then goes out, as it is waiting for the enable signal from the Master. When the slave has the "standalone firmware" installed, it comes on and stays on when you turn on its power. This is important; to verify the slave firmware is installed.
    6. If the Master and both Slaves can be seen via the WFM as I've just described, but after connecting them all together the Master is throwing the "no slave present" error (9 beeps), then there is one more thing to try. At some point I was unsure about the yellow/green wiring between the Master and Slave 1, and I switched those two wires at the Slave 1 14-pin connector. Then I think I switched it back; then I think when I was still getting error #9, I switched them once more, and it worked. The problem is, I'm not at all sure whether the yellow and green wires ended up exactly as shown in these diagrams, or reversed. It doesn't hurt to try switching the A and B lines of the RS485; so if everything else seems to be correct, perhaps try switching the green and yellow wires at the 14-pin. That is, green to #7 and yellow to #6.
    7. But be absolutely sure to turn off power and follow the reverse order as described in the manual, when disconnecting anything. And only switch the wires at the connector when it is hanging free and disconnected at both ends.
    8. Finally, to respond to your last question, about being specific as to colors and correct diagram for the 14-pin and 6-pin connectors, I stand by my assertion that the diagram I linked to [now] 18 hours ago is correct. But please be aware that when the slave has the proper "slave firmware", it is correct for it to only blink once briefly at power-up, because as a Slave it knows it has to wait for the enable signal from the Master. Any contactor it is powering won't kick in until you then start the Master (which should be done second), and only if the white enable wire is correctly connected.
    9. Not sure from my end as to why your WFM might not be doing anything at all when you power it up. That would sound like somehow it's actually NOT getting power.  Again a reminder to connect and power-up  everything according to the sequence in the manual.

    Good luck; hope this helps.

  • Rob

    @PeterD  got some work to do, great directions

    Rob tribble

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