https://forge.codesys.com/forge/talk/Engineering/thread/0b480ac73b/2020-02-27T14:00:40.411000ZRecent posts to Few Modbus TCP Master's in same Ethernet Adapter2020-02-27T14:00:40.411000Z2020-02-27T14:00:40.411000Ze.kislovhttps://forge.codesys.com/u/e-kislov/https://forge.codesys.comd1f9d29f89357003efdca8faf4ebea3b333130e2

<div class="markdown_content"><p>Yes.</p></div>

2020-02-27T14:00:39.645000Z2020-02-27T14:00:39.645000ZUlvishttps://forge.codesys.com/u/ulvis/https://forge.codesys.comc1f537abf5118f9ed74c6cdd007ae3217529d939

<div class="markdown_content"><blockquote> <p><strong>e.kislov hat geschrieben:</strong><br/> Max. 100 channels per slave</p> </blockquote> <p>So... 64 slaves x 100 channels = 6.400 channels per Master ?</p> <p>(1 channel ==1 read or 1 write telegram)</p></div>

2020-02-27T14:00:39.364000Z2020-02-27T14:00:39.364000Ze.kislovhttps://forge.codesys.com/u/e-kislov/https://forge.codesys.com1f2e98c3fb04fd1c36aa22901da7b4c35acc2746

<div class="markdown_content"><blockquote> <p><strong>Ulvis hat geschrieben:</strong><br/> But how many channels per slave?</p> </blockquote> <p>Max. 100 channels per slave</p></div>

2020-02-27T14:00:39.081000Z2020-02-27T14:00:39.081000ZUlvishttps://forge.codesys.com/u/ulvis/https://forge.codesys.comdffd0b43a237bf529191e77e47438a6a935188d1

<div class="markdown_content"><blockquote> <p><strong>e.kislov hat geschrieben:</strong><br/> Thanks. Honestly it's obvious.<br/> If there were no restriction (or 247 as upper limit) for slaves in Modbus TCP Master - I would have no questions.<br/> But my question not about specification Modbus TCP or TCP, I just wonder is this correct to use many Modbus TCP Master under same Ethernet Adapter node.<br/> Maybe it's unexpected-from-user solution and it will create problems for IO-drivers or something other...<br/> So I just want to get some advice from developers.</p> </blockquote> <p>Whooa,no response from Dev?<br/> I have a simmilar newbie question….. <br/> <strong>How many slaves/channels can be assigned to a Codesys device ?</strong><br/> (Docs and googling did not reveal this in a second or two.)</p> <p>From the above posts I get hint of 64 slaves per master.<br/> Multipple masters are possible.<br/> But how many channels per slave?<br/> And what is the total max? Depending on system memory or what?<br/> Probably a number that will fit in a ip subnet of 200+ device will be sufficient. Then again there may be multipple device ids behind an ip.<br/> Anyone?</p></div>

2020-02-27T14:00:38.268000Z2020-02-27T14:00:38.268000Ze.kislovhttps://forge.codesys.com/u/e-kislov/https://forge.codesys.com762948c1029593e4d31732e5b9167c081ac69281

<div class="markdown_content"><p>Thanks. Honestly it's obvious.<br/> If there were no restriction (or 247 as upper limit) for slaves in Modbus TCP Master - I would have no questions.<br/> But my question not about specification Modbus TCP or TCP, I just wonder is this correct to use many Modbus TCP Master under same Ethernet Adapter node.<br/> Maybe it's unexpected-from-user solution and it will create problems for IO-drivers or something other...<br/> So I just want to get some advice from developers.</p></div>

2020-02-27T14:00:38.022000Z2020-02-27T14:00:38.022000ZdFxhttps://forge.codesys.com/u/dfx/https://forge.codesys.com388eb798b266ae3132a54d4eca33cba8b8c0a2f9

<div class="markdown_content"><p>As modbus TCP relies on TCP, the only limit I see is from IP addressing/subnets.<br/> Standard modbus applies only if your communication is in between modbus RTU/TCP gateways (so you need the use of the slave identifier, which is 0-254).</p></div>

2020-02-27T14:00:37.771000Z2020-02-27T14:00:37.771000Ze.kislovhttps://forge.codesys.com/u/e-kislov/https://forge.codesys.com72d9397228cdb72d717b86621106d10feeb624fa

<div class="markdown_content"><p>Hi.<br/> As we know, there is some limits for Modbus TCP Slave quantity under Modbus TCP Master - 32 devices (64 since SP13).<br/> I have many devices and as workaround I use many Modbus TCP Masters with 32 devices in each of them.<br/> Seems like it works but I want to understand it this correct solution or potentially dangerous?</p></div>