Help needed in reading milling machine electrical diagrams - Page 1
Forum section: electronics / beginners

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 10:51:36 am
content: Hi, can you guys help me out with figuring out few things on electrical diagrams for machine I bought recently ? Its 1985 Japanese milling machine with Fanuc 11m control. This is diagram for 5KW spindle motor:Pls take a look at sections marked on the pictures.1. Is this wire gauge ? I see it all over the diagram sometimes it says 3.5° here I think it says 5.5°2. Is this fan motor ?3. I assume this is encoder (resolver?). Is it possible just by looking at the wiring to say what type of device it is? PA, RA, PB, RB are differential lines? Why two lines.4. Is this shielding ? SS symbol does this indicate something? I usually saw shielding connected to ground.Thank you in advance.

author: Benta
author_rank: Super Contributor
timestamp: November 08, 2020, 12:26:05 pm
content: 1: don't think so. More likely a wire label pointing to a different part of the schematic.2: I see it as the exciter coil for the resolver.3: PA, PB, RA, RB are the 90 degrees offset detector coils of the resolver4: SS is shield.Scratch this. I agree with Renate.

author: Renate
author_rank: Super Contributor
timestamp: November 08, 2020, 12:50:13 pm
content: FM=Fan motorPG=Pulse generatorI would wonder if the pulse generator is possibly an optical encoder since it gets 5 V.PA, PB=pulse? RA, RB=reference?It should be easy enough to disconnect and check a few resistances.

author: Twoflower
author_rank: Frequent Contributor
timestamp: November 08, 2020, 01:26:14 pm
content: To Point 1: I've seen sometimes a little raised box to indicate mm^2. But that in combination with 5.5 (or 3.5) seems not to make much sense as this are not normal cable sizes.

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 02:36:16 pm
content: Quote from: Twoflower on November 08, 2020, 01:26:14 pmI see those all over the place. Here is another exampleBtw do you know why attaching images inline does not work. Is it normal for this forum engine?

author: drussell
author_rank: Super Contributor
timestamp: November 08, 2020, 03:51:47 pm
content: Quote from: lkuchars on November 08, 2020, 02:36:16 pmYes. It has been broken for months.Inline attachments are currently just completely disabled due to ongoing issues where posts would pull images from other posts or new inline images would overwrite old ones. It has been broken ever since Dave, Simon,gnifet al. did the last SMF update. It has been extensively discussed in multiple threads including the TEA thread, the Sever Errors thread as well as a bunch of individual threads in places like General Chat and the EEVblog Suggestions topic.eg:https://www.eevblog.com/forum/chat/website-error-reports/msg3107598/#msg3107598

author: ace1903
author_rank: Regular Contributor
timestamp: November 08, 2020, 03:56:23 pm
content: I have seen this format to be used in the form: the first number is the number of wires in the cable, the second number is the wire area and the box means that the cable has a shield. so 5.5 means small signal cable with 5 wires each 0,5mm2 and wires are under a common shield.But here doesn't make sense because wire for the spindle is likely more than 0,5mm2.

author: Twoflower
author_rank: Frequent Contributor
timestamp: November 08, 2020, 03:59:21 pm
content: Can you check the cable itself? Maybe it has some type printed on. Or measure the diameter. As it is indeed a square it could mean mm^2 but you should definitely double-check that. It seems that 3.5 and 5.5mm^2 surface areas are defined by the JIS (Japanese Industrial Standards).

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 05:27:05 pm
content: Quote from: Twoflower on November 08, 2020, 03:59:21 pmI'm still waiting for the machine to be shipped. Thank you. Once I figure it out I'll let U guys know.

author: Benta
author_rank: Super Contributor
timestamp: November 08, 2020, 05:43:59 pm
content: Quote from: Twoflower on November 08, 2020, 03:59:21 pmI can confirm that. JIS has 3.5 mm2and 5.5 mm2as standard cross-section copper area. And as the connections indicated are all high current, 3-phase buses, this would make sense.EU standards are 4.0 mm2and 6.0 mm2.And the symbols do look like a small square, which is the symbol for cable size.

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 05:48:54 pm
content: Ok thank you. Another question. How are these tables called. Is there standardized way to read them ? Why there are three rows everywhere. Can't be such huge connectors right?

author: Twoflower
author_rank: Frequent Contributor
timestamp: November 08, 2020, 05:57:02 pm
content: That looks like the connector as seen from the controller (or any terminal block in the machine). Most likely it looks similar in the machine itself. It helps you to find measurement points.For example in the first picture you see in the lower left "CN1" and position 18 and 49. On the connector sheet you find the connector CN1 and see that the terminals 18 and 49 are connected (and the target of the connection).Edit: CN looks actually like a connector if you look closely in the first picture. There are two parts noted with CN1. And right to it is a connector terminal (with a C label).Edit II: The connector type is listed right next to the CNxxx. On that page onlyMR-50RFWused.

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 07:05:56 pm
content: Quote from: Twoflower on November 08, 2020, 05:57:02 pmThose diagonal lines indicate that terminals are connected ?So 18 <-> 49and 17 <-> 48?

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 07:09:00 pm
content: They are connected via Load Meter ? Like this ?

author: Twoflower
author_rank: Frequent Contributor
timestamp: November 08, 2020, 07:29:03 pm
content: Those diagonal marked pins are probably not there at all like removed pins (stroke through).It will look like:Controller module has a socket (CN1.49) <--> Connector CN1.49<--cable-->C103.39<--cable-->Loadmeter (LM1)Controller module has a socket (CN1.18) <--> Connector CN1.18<--cable-->C103.40<--cable-->Loadmeter (OM)

author: lkuchars
author_rank: Contributor
timestamp: November 08, 2020, 08:07:29 pm
content: I get it. Thank You. To be honest I did not realize by first time looking at them that they are just layouts of which pin connects to which point in the circuit.

author: Twoflower
author_rank: Frequent Contributor
timestamp: November 08, 2020, 08:15:20 pm
content: Yes, in industrial wiring sheets you'll find them often. Even if seems to be redundant information it helps if you try to fix the machine in the field.