nodes7comm

nodes7comm

This library allows communication to S7-300/400/1200/1500 PLCs using the Siemens S7 Ethernet protocol.

This library is based entirely from nodeS7.

Get Started

• First you need to enable GET/PUT Access. Right click on PLC -> Properties -> Protection and security -> Connections mechanisms -> Check GET/PUT Access.
• For access to a DB you must disable Optimized Block Access in TIA Portal for that DB. Right click on DB -> Properties -> Attributes -> Uncheck Optimized Block Access.
• More info: snap7

Installation

npm install nodes7comm

Methods

• initiateConnection
• readTags
• writeTags
• addTranslationTags
• deleteTranslationTag
• addTags
• readAllTags
• removeTags

initiateConnecton

import { NodeS7Comm, Nodes7CommConfig } from 'nodes7comm';

const options: Nodes7CommConfig = {
    host: '192.168.1.200',
};

const s7Client = new NodeS7Comm(options);
s7Client.initiateConnection();

s7Client.on('error', (err) => {
	// Error events
});

s7Client.on('disconnected', () => {
	// When we are reading or writing and a timeout ocurred
});

s7Client.on('connected', () => {
	// When we connect to the PLC
});

s7Client.on('connect-timeout', () => {
	// When we are unable to establish a connection
});

Nodes7CommConfig: Interface

propertie	type	required	default	description
host	string	true		Address of the PLC
port	number	false	102	Port to stablish connection
rack	number	false	0	Rack of PLC
slot	number	false	1	Slot of PLC
connectionTimeout	number	false	5000	Timeout to establish a connection
requestTimeout	number	false	1500	Timeout of each request
localTSAP	number	false
remoteTSAP	number	false
connectionName	string	false	${host}
optimize	boolean	false	true	Enable optimization of packages sent to PLC
autoReconnect	boolean	false	true	Auto connect after disconnect
logLevel	'none' 'error' 'warn' 'info'	false	'none'	Show logs in console

readTags

// This function read values in given plc directions
s7Client.readTags('Q0.0').then((value) => {
	console.log(value); // { 'Q0.0': false }
});

s7Client.readTags(['DB100,REAL22', 'M0.0']).then((values) => {
	console.log(values); // { 'DB100,REAL22': 20.5, 'M0.0': false }
});

writeTags

// This function write values in given plc directions
s7Client.writeTags('Q0.0', false).then((newValues) => {
	console.log(newValues); // { 'Q0.0': false }
});

// Arrays must have same length
s7Client.writeTags(['DB100,REAL22', 'DB99,S0.50'], [32.3, 'Hello' ]).then((newValues) => {
	console.log(newValues); // { 'DB100,REAL22': 32.3, 'DB99,S0.50': 'Hello' }
});

addTranslationTags

// This function add a name to each directions, for better manage for your app

const tags = {
    analog: 'DB100,REAL22',
    name: 'DB99,S0.50',
    output: 'Q0.0',
};

s7Client.addTranslationTags(tags);

// Note that this time we are reading the keys of the above object
s7Client.readTags(['analog', 'name', 'output']).then((values) => {
	console.log(values); // { analog: 32.29999923706055, name: 'Hello', output: true }
});

const moreTags = {
    active: 'DB100,X0.0',
};

s7Client.addTranslationTags(moreTags);

// Apply on writeTags() too
s7Client.writeTags(['analog', 'active'], [50.5, true]).then((values) => {
    console.log(values); // { analog: 50.5, active: true }
});

deleteTranslationTag

// Delete a tag from translation object
s7Client.deleteTranslationTag('analog');

s7Client.readTags('analog').then((values) => {
    console.log(values);
}).catch(err => {
    console.log(err); // Failed to find a match for: analog
});

addTags

// We can save tags in the instance for read all stored tags
s7Client.addTags(['DB100,X0.0']);

const tags = {
    input: 'I0.0',
    tagBool: 'M6.4',
};
s7Client.addTranslationTags(tags); // If we want to store alias, we need first add these tags in the traslation

s7Client.addTags(Object.keys(tags)); // Array of tags

readAllTags

const tags = {
    input: 'I0.0',
    tagBool: 'M6.4',
};
s7Client.addTranslationTags(tags);

// Add he keys of the abject above
s7Client.addTags(Object.keys(tags));

s7Client.readAllTags().then((values) => {
    console.log(values); // { input: false, tagBool: false }
});

removeTags

// Remove tags from the instance
s7Client.removeTags('input');

s7Client.readAllTags().then((values) => {
    console.log(values); // { tagBool: false }
});

Supported address

Operand identifier	Data type	Examples
Input (I)	Bool Byte Char Word Int DWord DInt Real LReal	I1.0 IB3 IC4 IW22 II24 ID26 ID140 IR1400 ILR1404
Output (Q)	Bool Byte Char Word Int DWord DInt Real LReal	Q0.2 QB2 QC4 QW20 QI22 QD24 QDI28 QR32 QLR36
Memory (M)	Bool Byte Char Word Int DWord DInt Real LReal	M2.2 MB0 MC2 MW220 MI28 MD40 MD100 MR2000 MLR2004
Data Block (DB)	Bool Byte Char Word Int DWord DInt Real LReal String	DB5,X2.2 DB6,B0 DB10,C2 DB10,W220 DB10,I28 DB12,D40 DB2,D100 DB100,R2 DB101,LR6 DB99,S0.50