Modbus RTU Failure

General
1

Hi, I´m using a RS485 -> USB Donlge ( DSD TECH SH-U11F) since 12/2021 with 4x Eastron SDM meter.
Until last month I used 3x SDM72v2 & 1xSDM230 with 9600 baud.

last month I replaced SDM230 to SDM630v2.

With SDM630v2 I get sometimes every minute, sometimes after 10 minutes Modbus failures:
mod

I tried 19200 and 9600 Baud - same problem.

Any ideas what´s the problem ?

The SDM230 and now SDM630v2 is the last meter on the modbus, but it is adress #3.
could this be the problem ? the order of the id doesn't matter to the physical order in bus?

I also tried connection delay 0,1,5ms; different queue delays.

the error always comes from the SDM630:

grafik
grafik501×666 48.6 KB

manual:

Modbus flow:

[
    {
        "id": "fe9c25b2603b8f3f",
        "type": "inject",
        "z": "112d382639b7cc28",
        "name": "alle 2s",
        "props": [
            {
                "p": "payload"
            }
        ],
        "repeat": "2",
        "crontab": "",
        "once": false,
        "onceDelay": "10",
        "topic": "",
        "payload": "true",
        "payloadType": "bool",
        "x": 180,
        "y": 60,
        "wires": [
            [
                "8a5957b7b2f7ec03"
            ]
        ]
    },
    {
        "id": "8a5957b7b2f7ec03",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0006 - 0035",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "1",
        "dataType": "InputRegister",
        "adr": "0006",
        "quantity": "30",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 100,
        "wires": [
            [
                "f20df6cb188e76a4"
            ],
            [
                "b267ca8a8b7f6dcb"
            ]
        ]
    },
    {
        "id": "b267ca8a8b7f6dcb",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0052 - 0053",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "1",
        "dataType": "InputRegister",
        "adr": "0052",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 160,
        "wires": [
            [
                "e58032fe783749bd"
            ],
            [
                "268716dd0510b280"
            ]
        ]
    },
    {
        "id": "268716dd0510b280",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0060 - 0063",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "1",
        "dataType": "InputRegister",
        "adr": "0060",
        "quantity": "4",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 220,
        "wires": [
            [
                "a4cf714520032bd0"
            ],
            [
                "c7d78de48b6972f0"
            ]
        ]
    },
    {
        "id": "c7d78de48b6972f0",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0070 - 0075",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "1",
        "dataType": "InputRegister",
        "adr": "0070",
        "quantity": "6",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 280,
        "wires": [
            [
                "2ae4692b297de57f"
            ],
            [
                "3a7729b29e4a9e67"
            ]
        ]
    },
    {
        "id": "3a7729b29e4a9e67",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0224 - 0225",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "1",
        "dataType": "InputRegister",
        "adr": "0224",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 340,
        "wires": [
            [
                "19f9bcad6ccfb90d"
            ],
            [
                "44049c9369ec07d6"
            ]
        ]
    },
    {
        "id": "b9a429ba348a3d94",
        "type": "comment",
        "z": "112d382639b7cc28",
        "name": "ID2 PV-Erzeugung",
        "info": "",
        "x": 210,
        "y": 520,
        "wires": []
    },
    {
        "id": "219a2f38e1290dc1",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0052 - 0053",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "0052",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 620,
        "wires": [
            [
                "b0d2e266bd07228e"
            ],
            [
                "bb8ffd892da9597a"
            ]
        ]
    },
    {
        "id": "bb8ffd892da9597a",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0060 - 0063",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "0060",
        "quantity": "4",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 680,
        "wires": [
            [
                "cddffc4f7547293c"
            ],
            [
                "ef109eceec75d7b3"
            ]
        ]
    },
    {
        "id": "44049c9369ec07d6",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0006 - 0035",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "0006",
        "quantity": "30",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 560,
        "wires": [
            [
                "74a43fce665f37f7"
            ],
            [
                "219a2f38e1290dc1"
            ]
        ]
    },
    {
        "id": "ef109eceec75d7b3",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0070 - 0075",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "0070",
        "quantity": "6",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 740,
        "wires": [
            [
                "dd2c48ebe743a6db"
            ],
            [
                "4de1cd7200f7a98d"
            ]
        ]
    },
    {
        "id": "4de1cd7200f7a98d",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0224 - 0225",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "0224",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 800,
        "wires": [
            [
                "faa4e44ff116b3b3"
            ],
            [
                "f8dd7823b25fa4ca"
            ]
        ]
    },
    {
        "id": "f8dd7823b25fa4ca",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0396 - 0397",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "0396",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 860,
        "wires": [
            [
                "f978b71e6bc35213"
            ],
            [
                "76ba54f6f0231b28"
            ]
        ]
    },
    {
        "id": "76ba54f6f0231b28",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "1280 - 1283",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "2",
        "dataType": "InputRegister",
        "adr": "1280",
        "quantity": "4",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 920,
        "wires": [
            [
                "dbec47e366616491"
            ],
            [
                "79b2e1e0a77fa7ed"
            ]
        ]
    },
    {
        "id": "79b2e1e0a77fa7ed",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0000 - 0035",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0000",
        "quantity": "36",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1160,
        "wires": [
            [
                "7cef9c2ca3205b9a"
            ],
            [
                "3132c8d4c29db3a8"
            ]
        ]
    },
    {
        "id": "3132c8d4c29db3a8",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0052 - 0053",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0052",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1220,
        "wires": [
            [
                "505753fe829e972c"
            ],
            [
                "53cef9e918cc1143"
            ]
        ]
    },
    {
        "id": "53cef9e918cc1143",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0060 - 0063",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0060",
        "quantity": "4",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1280,
        "wires": [
            [
                "7797ae9f85a1fb73"
            ],
            [
                "e7798e5bcc295ca1"
            ]
        ]
    },
    {
        "id": "e7798e5bcc295ca1",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0066 - 0067",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0066",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1340,
        "wires": [
            [
                "78559fb9acfabea7"
            ],
            [
                "2f888de6f12d3302"
            ]
        ]
    },
    {
        "id": "2f888de6f12d3302",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0070 - 0075",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0070",
        "quantity": "6",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1400,
        "wires": [
            [
                "6bc647f3eed0237d"
            ],
            [
                "96d78a453c1be222"
            ]
        ]
    },
    {
        "id": "96d78a453c1be222",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0200 - 0205",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0200",
        "quantity": "6",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1460,
        "wires": [
            [
                "3dcd3d822dcb0791"
            ],
            [
                "61864da55a579e34"
            ]
        ]
    },
    {
        "id": "61864da55a579e34",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0224 - 0225",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0224",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1520,
        "wires": [
            [
                "98d85cb9885c1629"
            ],
            [
                "a754c17f5e94cbc5"
            ]
        ]
    },
    {
        "id": "a754c17f5e94cbc5",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0234 - 0245",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0234",
        "quantity": "12",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1580,
        "wires": [
            [
                "e36e1371e8754686"
            ],
            [
                "3a602ae73dba50b9"
            ]
        ]
    },
    {
        "id": "3a602ae73dba50b9",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0342 - 0363",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "3",
        "dataType": "InputRegister",
        "adr": "0342",
        "quantity": "22",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1640,
        "wires": [
            [
                "bfe47de4f4b0124d"
            ],
            [
                "2844c4c58b7e4729"
            ]
        ]
    },
    {
        "id": "2844c4c58b7e4729",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0006 - 0035",
        "showStatusActivities": false,
        "showErrors": true,
        "showWarnings": true,
        "logIOActivities": false,
        "unitid": "4",
        "dataType": "InputRegister",
        "adr": "0006",
        "quantity": "30",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "delayOnStart": false,
        "startDelayTime": "",
        "x": 190,
        "y": 1820,
        "wires": [
            [
                "ac1cea62248307c0"
            ],
            [
                "15b9f2ce6c23e859"
            ]
        ]
    },
    {
        "id": "15b9f2ce6c23e859",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0052 - 0053",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "4",
        "dataType": "InputRegister",
        "adr": "0052",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 1880,
        "wires": [
            [
                "547a95a8fa761ce4"
            ],
            [
                "385f6eb8bf7fc2fb"
            ]
        ]
    },
    {
        "id": "c2e327bbc7e4e03d",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0224 - 0225",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "4",
        "dataType": "InputRegister",
        "adr": "0224",
        "quantity": "2",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 2060,
        "wires": [
            [
                "cf19175fce13241f"
            ],
            [
                "de1058be122d0f68"
            ]
        ]
    },
    {
        "id": "385f6eb8bf7fc2fb",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0060 - 0063",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "4",
        "dataType": "InputRegister",
        "adr": "0060",
        "quantity": "4",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 1940,
        "wires": [
            [
                "2f25dd3b2d0c1467"
            ],
            [
                "b37015d4bf776d74"
            ]
        ]
    },
    {
        "id": "b37015d4bf776d74",
        "type": "modbus-getter",
        "z": "112d382639b7cc28",
        "name": "0070 - 0075",
        "showStatusActivities": false,
        "showErrors": true,
        "logIOActivities": false,
        "unitid": "4",
        "dataType": "InputRegister",
        "adr": "0070",
        "quantity": "6",
        "server": "bb0f2e018eb97236",
        "useIOFile": false,
        "ioFile": "",
        "useIOForPayload": false,
        "emptyMsgOnFail": false,
        "keepMsgProperties": false,
        "x": 190,
        "y": 2000,
        "wires": [
            [
                "45c1c62ce6779015"
            ],
            [
                "c2e327bbc7e4e03d"
            ]
        ]
    },
    {
        "id": "bb0f2e018eb97236",
        "type": "modbus-client",
        "name": "SDM",
        "clienttype": "serial",
        "bufferCommands": true,
        "stateLogEnabled": false,
        "queueLogEnabled": false,
        "failureLogEnabled": false,
        "tcpHost": "127.0.0.1",
        "tcpPort": "502",
        "tcpType": "DEFAULT",
        "serialPort": "/dev/ttyUSB0",
        "serialType": "RTU-BUFFERD",
        "serialBaudrate": "9600",
        "serialDatabits": "8",
        "serialStopbits": "1",
        "serialParity": "none",
        "serialConnectionDelay": "5",
        "serialAsciiResponseStartDelimiter": "0x3A",
        "unit_id": 1,
        "commandDelay": 5,
        "clientTimeout": 3000,
        "reconnectOnTimeout": true,
        "reconnectTimeout": 5000,
        "parallelUnitIdsAllowed": false
    }
]

I don´t use resistors (120ohm) - the length is only 1-1,5m.
should I use ?

greetings

2

Hello Becker .. Hows it going ?
I read in section 3.3 (page 40) from the manual

In the Eastron 1000 and 2000, a silent interval of 60msec minimum is required in order to guarantee successful reception of the next request.

you mentioned that you tried connection delay 0,1,5ms; different queue delays.

Have you tried anything higher than 60ms as mentioned in the manual ?

1 Like
3

thank you, I actually didn't read that :roll_eyes:

with 60ms it´s very slow - for all meters I need 3s, but without errors.

I think I have to buy a 2nd RS485-USB, just for the SDM630v2.

I also will try a 120 Ohm resistor at the end, but I think it´s unnecessary.

Maybe the SDM72v2 don´t need 60ms. I runs over a year with 5ms..

4

good that you dont have errors any more .. and yes that would increase the overall time to request all registers but .. you could try merging (grouping) some of your requests to shave off some ms.

From the Modbus RTU protocol spec we know that the maximum request of registers you can make is 125 registers

so based on the screenshot you shared you can try to group / request more registers in each call
For ID3 instead of 9 requests you can drop it down to 3 (0 to 75 , 200 to 245, 342 to 363 etc)

image
image499×667 61.7 KB

5

the manual say max. 40 at once !

·Each request for data must be restricted to 40 parameters or less. Violating this requirement will impact
the performance of the instrument and may result in a response time in excess of the specification.

I bought a 2nd RS485 USB adapter :wink:

1 Like
6

Can you tell me about "connection delay" (ms) ?
what impact/influence does that have?

7

For Connection delay .. its not mentioned in the help tab but i think its the initial delay before the serial connection is established. which is different from the Queue delay (ms) which is the delay just before each modbus register request.

I dont think this would affect the issue you are experiencing since you get errors not with the first request but later after a few minutes.

8

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.