Endress+Hauser NXA820, NXA821, NXA822 Specifications

Technical Information

Tankvision NXA820, NXA821, NXA822

Inventory Management System with completely integrated software

for operation via standard web browser

Application

Tankvision is a dedicated tank inventory system which is operated by a standard web browser and does not require proprietary software or licensing costs.

Tankvision is based on a distributed architecture on a Local Area Network (LAN). Due to its modular structure it can be adjusted to any application. It is ideally suited for small tank farms with only a couple of tanks, but also for large refineries with hundreds of tanks.

Tankvision consists of the following components:

• Tankvision NXA820 (Tank Scanner)

scans parameters from tank gauges and performs tank calculations

• Tankvision NXA821 (Data Concentrator) summarizes data from various Tank Scanners NXA820

• Tankvision NXA822 (Host Link)

provides data to host systems (such as PLC or DCS) via Modbus

Your benefits

• License-free

• Approved for custody transfer applications according to NMI and PTB (in preparation)

• Global system engineering and service support

• A robust industrial operating system with embedded software ensures high stability and availability.

• Modular design; easily adjustable to any application; can be upgraded as required

• Configuration, commissioning and operation via web browser; no proprietary software required

• Access for up to 10 users per Tankvision component from any connected PC

• Common hardware platform for all components; no hard disc or fans - no wearout

• Volume calculations and correction included according to international standards (API/ASTM/IP tables) in Tank Scanner NXA820

• Predefined or customized operator screens for typical operation of a tank farm

TI419F/00/en/05.08

Tankvision NXA820, NXA821, NXA822

Table of Contents

Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Inventory control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Inventory calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Remote configuration of measuring equipment . . . . . . . . . . . . . . . 3 Application areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Function and system design. . . . . . . . . . . . . . . . . . . . . 4

System design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 System configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Typical system configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Tankvision NXA820 (Tank Scanner) . . . . . . . . . . . . . . 7

Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Number of tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 LAN connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Input NXA820 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Output NXA820 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Power supply NXA820 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Terminals NXA820 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Ambient conditions NXA820 . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Mechanical construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Human interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Certificates and approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Ordering information NXA820 . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Tankvision NXA821 (Data Concentrator) . . . . . . . . . 19

Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Number of tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 LAN connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Output NXA821 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Terminals NXA821 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Ambient conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Mechanical construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Human interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Certificates and approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Ordering information NXA821 . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Tankvision NXA822 (Host Link) . . . . . . . . . . . . . . . . 27

Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Number of tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 LAN connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Output NXA822 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Terminals NXA822 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Ambient conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Mechanical construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Human interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Certificates and approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Ordering information NXA822 . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Human interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Operating concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Languages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 System requirements

of user PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Examples of operating pages . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Supplementary documentation . . . . . . . . . . . . . . . . . 40

Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Description of Instrument Functions . . . . . . . . . . . . . . . . . . . . . . 40

Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

MODBUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Java . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

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	Applications
Inventory control	By using Tankvision to monitor the tank level and stored volume of valuable liquids remotely, owners or
	operators of tank farms or terminals for petroleum products and chemicals (liquids) can visualize the volume
	of the stored medium in real time. The data can be used to plan the inventory and distribution. The data can
	also be used to manage tank farm operations like pumping or transferring products.
	Tankvision has its unique concept using network technology. Without using proprietary software, the users can
	visualize and manage their valuable liquids stored in the tanks by a web browser.
	Tankvision is a flexible and cost effective solution due to its scalable architecture. The application coverage goes
	from small depots with only a few tanks up to refineries.
Inventory calculations	Tankvision calculates gross, net volumes and mass, based on measured variables and tank capacity tables.
	Volumes and density of products like hydrocarbons, LPG's, asphalt are corrected according to international
	standards, including API/ASTM tables 5A, 5B/6, 53A, 53B/54, 23/24, LPG. This includes temperature
	corrections at 15C, 60F and alternative temperatures. Additionally, available pumpable volumes and water
	volume are calculated. Up to 3000 strapping points per tank are supported for vertical, spherical and bullet
	tanks.
Remote configuration of	Tankvision does not only acquire the current measured level or volume from the tanks. The configuration of
measuring equipment	device settings from the control room is also possible by using the corresponding HART operating software from
	Endress+Hauser (e.g. ToF Tool or FieldCare) for the connected Endress+Hauser devices. Tankvision passes on
	the device setting information transparently, so that all device functions for the respective operating software
	are available from the control room. Some on-site operations can be avoided using this feature during
	commissioning or maintenance. (The availability of this feature may depend on the system configuration.)
Application areas	• tank farms in refineries
	• ship loading terminals
	• marketing and distribution terminals
	• pipeline terminals
	• logistic terminals for tanks storing products like crude oils, refined white and black products, chemicals,
	LPGs

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	Function and system design
System design	Tank management visualization without proprietary software
	Tankvision is the first tank management visualization system providing its functionality without the need to
	have proprietary software installed and maintained on a PC. The main functionality is realized by embedded
	web pages in the Tankvision components. Tankvision uses an industrial proven operating system and provides
	high availability. Tankvision is not based on a PC platform and runs independent of connected PCs. This
	eliminates the need to maintain a specialized PC with a Windows operating system and necessary updates and
	hot fixes. Tankvision web pages can be accessed from a standard PC with a web browser and the Java Runtime
	Environment only. Multiple users with different roles can simultaneously log in to each Tankvision component.
	Additional users can be added as required. There are no multi-user licence fees.
	Distributed architecture and scalability
	Tankvision is based on a distributed architecture on a Local Area Network (LAN). Coordinated components
	perform all inventory management tasks. The modular design makes it easy to enlarge the system whenever
	required and to add further tank areas.
	Thus, Tankvision is fully scalable and is ideally suited for applications of any size - from small tank farms to
	large refineries.
	Common hardware platform
	The Tankvision components have dedicated tasks in a system, but have a common architecture, based on a 32
	Bit processor. The embedded tank management software uses a multi-threaded real time operating system
	(RTOS), specifically designed for industrial applications. The hardware is designed without wear-out
	components like hard discs or fans. This guarantees high reliability.
System configuration	Configuration of the components
	Each Tankvision component has its own data base and a web server. The components are connected and
	exchange data with time stamp and status information. Data is optionally encrypted and secured by a CRC
	checksum.
	The Tankvision components are configured with static IP addresses, which are reserved on a DHCP network.
	The configuration pages are embedded in the Tankvision components and allow configuration of Tankvision
	via a connected web browser without configuration software. No Internet access is necessary, as all pages are
	loaded from the Tankvision system itself.
	Configuration of the connected tank gauges/sensors
	(available for Windows XP SP1; in preparation for Windows XP SP2)

Tankvision supports connection of Endress+Hauser configuration tools (e.g. ToF Tool or FieldCare) via LAN.

This enables configuration of the tank gauges if they support remote configuration (e.g. Tank Side Monitor

NRF590 and the level radars Micropilot S FMR53x/FMR54x).

The tank gauges must be connected to the Tank Scanner NXA820 in one of the following ways:

•via a field protocol

•via HART to the Tank Side Monitor NRF590 (version 02.04) which in turn is connected via one of the following protocols to the Tank Scanner NXA820:

–MODBUS

–Sakura V1

–Whessoematic WM550 (in preparation)

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Features	• Representation of tank data
	Tank data can be represented graphically or in tables. The corresponding HTML pages are predefined.
	• Definition and management of tank groups
	The total contents of static or dynamic tank groups (e.g. of tanks containing the same product) can be
	displayed.
	• Definition and management of products
	Product characteristics can be defined. The defined product can be attributed to a number of tanks. Links to
	product safety sheets can be integrated.
	• Trend display
	Real time and historical trends of the tank parameters can be displayed. The data is stored in the internal
	memory.
	• Archive
	Tankvision stores measured and calculated data, log files and alarms on the internal flash memory.
	• Alarms
	Limit alarms (high-high, high, low, low-low) can be defined for measured and calculated tank parameters.
	An alarm bar visualizes alarms in the browser window.
	Alarms can be reported by an optional Alarm Popup1) window.
	• Products
	A product database allows definition of 250 products per NXA or shared in the system.
	• Monitoring of transfers
	Product transfers from and to tanks can be monitored. Pre-alarms can be generated before completion of the
	transfer. A report is issued after the transfer.
	• Auditing
	An auditing table contains all events such as alarms or configuration changes.
	• Log-In roles
	Log-In roles with different access rights (supervisor, operator, guest) can be assigned to users and user
	groups.
	• Reports
	Reports are predefined as HTML pages. They can be sent to a printer connected to a computer at scheduled
	time intervals by an optional Printer Agent1.
	• Volume calculation and correction
	Available calculation tables according to API, ASTM and IP can be integrated.
	• Graphical User Interface (GUI)
	Tankvision uses an intuitive and optimized user interface (e.g. automatic creation of dynamic tank groups).
	• Remote access
	Any PC with the specified requirements which is connected to the Intranet can be connected with
	Tankvision.
	• Redundancy (in preparation)
	Two Tankvision components of the same type can be interconnected via the SyncLink interface. Only the
	primary NXA has to be configured. The secondary NXA takes over the task if the master fails (see diagram
	on page 6).

1)available for Windows on the device to upload; other operating systems in preparation

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Typical system configurations

Small tank farm (up to 15 tanks)

Browser

PLC

NXA822

Switch

OPC Server

	NXA822
	Host Link
	NXA820
	NXA820
FieldCare/	Tank Scanner
ToF Tool
	Fieldbus protocol (e.g. MODBUS, V1, WM550*)

*in preparation

	Prothermo
Micropilot	Prothermo

Proservo

Tank Side
Monitor	Promonitor

L00-NXA82xxx-02-00-00-en-001

Refinery (up to 225 tanks)

					Operator 1
DCS	NXA822		NXA821
	Host Link	Data Concentrator
					Operator 2
(redundant)			(redundant)		Operator 3
				Ethernet
			Switch
NXA820		NXA820		NXA820	NXA820
				(redundant)
Tank Scanner	Tank Scanner				Tank Scanner
Fieldbus protocol			Fieldbus protocol		Fieldbus protocol
					L00-NXA82xxx-02-00-00-en-002
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Tankvision NXA820, NXA821, NXA822

		Tankvision NXA820 (Tank Scanner)
	Function	• The Tank Scanner NXA820 connects multiple tank gauges from up to 15 tanks via one field-loop. The Tank
		Scanner NXA820 supports different field protocols (Modbus EIA485, Sakura V1, Whessoematic WM550).
		• The measured values are transmitted by the network and visualized on HTML pages.
		• The Tank Scanner NXA820 can be used stand-alone for small tank farms, but also be integrated into a large
		system for use in refineries.
		• The Tank Scanner NXA820 is equipped with a full set of tank inventory calculations. The calculations are
		based on various international standards such as API, ASTM, IP and many others. Measured values are used
		to calculate volume and mass.
	Number of tanks
		Protocol	max. number of tanks per NXA820
		MODBUS EIA485	15
		Sakura V1	10
		Whessoematic WM550	15
		(in preparation)
	LAN connections	System LAN port
		100 BASE-TX, Full/Half Duplex, 100 Mbit, Shielded RJ45 connector
		Connects the NXA820 Tank Scanner to the Local Area Network (LAN)

Sync-Link LAN port (in preparation)

100 BASE-TX, Full/Half Duplex, 100 Mbit, Shielded RJ45 connector

Connects the NXA820 Tank Scanner (e.g. primary) to an optional redundant unit (e.g secondary), to make sure the two devices remain synchronized with each other. If the primary unit fails, the secondary NXA820 Tank Scanner takes over operation without system interruption (see diagram on page 6).

Service LAN port

100 BASE-TX, Full/Half Duplex, 100 Mbit, Shielded RJ45 connector

Connects the NXA820 Tank Scanner to a local computer only for local commissioning and service operations. The computer does not become part of the local area network the NXA820 Tank Scanner is connected to through the System LAN port.

This port has a fixed IP address and can also provide the connected computer automatically with a compatible IP address using a DHCP server built into the NXA820 Tank Scanner. For this automatic IP function to work the computer must be set to obtain its IP address using a DHCP server

!Note!All LAN ports support Auto-MDIX. This system automatically detects the type of cable connected (either straight or crossed) and adjusts itself to match. With this feature you do not need to obtain special crossed cables to interconnect Tankvision components.

Input NXA820	Fieldbus protocols
	The Tank Scanner NXA820 is available with the following field protocols:
	• MODBUS EIA485 master, max. 15 gauges
	• Sakura V1, max. 10 gauges
	• Whessoematic 550, max. 15 gauges (in preparation)

Output NXA820	NXA Status Relay
	• potential free relay, SPDT
	• normally-closed when NXA is operating normally, open when NXA is powered off or in fault status
	• switching power:
	– 25 VDC, 100 W
	– 250 VAC, 4 A, 1000VA

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Tankvision NXA820, NXA821, NXA822

Power supply NXA820	Instrument version	Supply voltage	Power consumption	Current consumption	Fuse
	AC voltage	90 - 250 VAC	max. 23 VA	max. 100 mA at 230 VAC	400 mA T
	NXA820 - ##1########	(50/60Hz)
	DC voltage	10.5 - 32 VDC	max. 14 W	max. 580 mA at 24 VDC	2 A T
	NXA820 - ##2########

Galvanic isolation

The following terminals are galvanically isolated from each other:

•Alarm relay output

•LAN interfaces

•Fieldbus interface

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Terminals NXA820

A

B

C

POWER

10,5...32VDC

Fuse

2 A T

1 2 3

8 7 6

NXA Status

Relay

1 2 3

8 7 6

E

L-

L+

I J K

RESET

RESET

W &M

LH

10 11 12 13

10 11 12 13

MODBUS

F

D

E

G

L00-NXA82xxx-04-00-00-yy-019

A:Power supply; B: Fuse; C: Status relay; D: Fieldbus connection; E: Ground; F: System LAN port; G: Sync Link LAN port;

H:Service LAN port; I: Endress+Hauser CDI port; J: Display port; K: USB port; L: Weights & Measures locking switch

Power supply (AC version)

Terminal							Meaning	Remarks
1							L
								90 - 250 VAC
2							N
								Connector: Phoenix 7.62 GMSTB/GFKC
3							Potential equalization
							Fuse	400 mA T

Power supply (DC version)

Terminal							Meaning	Remarks
1							L+
								10.5 - 32VDC
2							L-
								Connector: Phoenix 7.62 GMSTB/GFKC
3							Potential equalization
							Fuse	2 A T

Status Relay

	Terminal	Meaning	Remarks
	6	normally open contact	•	NXA operating normally:
				terminals 7 & 8 are interconnected
	7	normally closed contact
			•	NXA powered off or fault status condition:
	8	switching contact		terminals 6 & 8 are interconnected

Connector: Phoenix FKC 2,5HC/3-St-5,08

!The depicted switching state of the relay refers to the de-energized state.Note!

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Tankvision NXA820, NXA821, NXA822

Field connection: MODBUS Serial, EIA/TIA-485 (RS485)

	Terminal	EIA/TIA-485	Meaning	Remarks
		MODBUS
	13	S	Capacitive Shield
	12	C	Signal Common	Connector: Phoenix FKIC 2,5/4-St-5,08
	11	B	+ signal
	10	A	- signal
	)	Ground		Must be independently connected directly to a primary
				grounding point using 4 mm2 cable.

Two-Wire MODBUS Definition

As described in the “MODBUS over serial line specification and implementation guide V1.02” published by the Modbus-IDA organisation (www.modbus.org) and based upon the EIA/TIA-485-A physical layer specification. MODBUS two-wire serial requires the following four electrical connections between each of the devices on the bus:

Signal	Purpose	Remarks
A	Data signal (-)	These signals must be connected using a balanced twisted pair cable.
B	Data signal (+)
C	Signal Common	Must interconnect all devices on the bus.
Shield	EMC Protection	Copper braided or combined foil and braided shielding.

Additional EIA/TIA-485 bus settings

•Bus biasing resistors (must be present at one point on the bus) (always enabled inside NXA820)

•Bus termination resistor (must be present at each end of the bus) (software selectable inside NXA820)

MODBUS Cable Specification

Characteristic impedance	135 to 165 Ω at measuring frequency of 3 to 20 MHz
Cable capacitance	≤ 30 pF/m
Core cross-section	≥ 0.34 mm2, corresponds to AWG 22, multi-strand cable is preferred
Cable type	Single twisted pair + third conductor (for common)
	or
	Dual twisted pair (common uses second pair with wire joined together)
Cable resistance	≤ 110 Ω/km
Signal damping	Max. 9 dB over the entire length of the cable cross-section
Shielding	Copper braided shielding or combined foil and braided shielding

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Field connection: V1

Terminal	V1		Meaning	Remarks
13		S	Capacitive Shield
12			Not connected	Connector: Phoenix FKIC 2,5/4-St-5,08
11		A	- signal
10		B	+ signal
)		Ground		Must be independently connected directly to a
				primary grounding point using 4 mm2 cable.

V1 Definition

V1 fieldbus is a voltage mode digital communication using up to ±30 VDC, and requires the following three electrical connections between each of the devices on the bus:

Signal	Purpose	Remarks
A	Data signal (-)	These signals must be connected using a balanced twisted pair cable.
B	Data signal (+)
Shield	EMC protection	Copper braided or combined foil and braided shielding

V1 Cable specification

Cable capacitance	≤ 50 nF/m
Core cross-section	≥ 0.9 mm2, corresponds to AWG 17, multi-strand cable is preferred
Cable type	twisted pair
Cable resistance	≤ 30 Ω/km
Shielding	Copper braided shielding or combined foil and braided shielding
Insulation	≥ 60 VDC

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Field connection: Whessoematic 550 (WM550) (in preparation)

	Terminal	WM550	Meaning	Remarks
	13		Not connected
	12		Not connected	Connector: Phoenix FKIC 2,5/4-St-5,08
	11	+	Loop Send
	10	-	Loop Return
	)	Ground		Must be independently connected directly to a
				primary grounding point using 4 mm2 cable.

WM550 Definition

WM550 fieldbus consists of a current loop which passes from the source device (e.g. NXA820) through all connected gauges before returning to the source device. Typically this is managed by a single multi-core cable which holds both the outgoing and returning current loop, and requires the following two electrical connections between each of the devices on the bus:

Signal	Purpose	Remarks
+	Current Loop (+)	Current always flows from positive to negative within the loop.
-	Current Loop (-)

"Caution!WM550 loop signal voltages can be as high as 100 VDC.

WM550 Cable specification

Cable capacitance	≤ 75 nF/m
Core cross-section	≥ 0.5 mm2, corresponds to AWG 20, multi-strand cable is preferred
Cable type	twisted pair
Cable resistance	≤ 40 Ω/km (total loop resistance ≤ 250Ω)
Shielding	None
Insulation	≥ 100 VDC

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Shielding and Grounding

When planning the shielding and grounding for a fieldbus system, there are three important points to consider:

•Electromagnetic compatibility (EMC)

•Explosion protection

•Safety of the personnel

To ensure the optimum electromagnetic compatibility of systems, it is important that the system components and above all cables, which connect the components, are shielded and that no portion of the system is unshielded. Ideally, the cable shields are connected to the normally metal housings of the connected field devices. Since these are generally connected to the protective earth, the shield of the bus cable is grounded many times. Keep the stripped and twisted lengths of cable shield to the terminals as short as possible.

This approach, which provides the best electromagnetic compatibility and personnel safety, can be used without restriction in systems with good potential equalization.

In the case of systems without potential equalization, a power supply frequency (50/60 Hz) equalizing current can flow between two grounding points which, in unfavourable cases, e.g. when it exceeds the permissible shield current, may destroy the cable.

To suppress the low frequency equalizing currents on systems without potential equalization, it is therefore recommended to connect the cable shield directly to the building ground (or protective earth) at one end only and to use capacitive coupling to connect all other grounding points.

The NXA820 provides two grounding points for the shield, close to the fieldbus interface connector:

•The “)” terminal, which should already be connected directly to ground

•The “S” terminal (13), which provides capacitive connection to the “)” terminal

"Caution!The legal EMC requirements are fulfilled only when the cable shield is grounded on both sides!

Endress+Hauser

13

Tankvision NXA820, NXA821, NXA822

LAN connection

Socket

Meaning

Remarks

System LAN port

Connects the instrument to the network.

Sync Link LAN port

Used for connection to redundant unit.

(in preparation)

If the primary unit fails, its task is taken over by the redundant unit.

Service LAN port

Connects the instrument to a computer locally for service purpose.

Only this instrument can be configured. The Service LAN port does not

allow access to the network.

LEDs

Symbol			Color	Meaning
			Green	Power On
			Yellow	Stand-by
				Indicates the box is a redundant secondary unit, and is ready to take over if the
				primary unit fails.
			Red	Fault
				Indicates a Fault when lit or "Maintenance required" when flashing
			Yellow	Communication
				Flashes when the NXA820 Tank Scanner completes a successful fieldbus
				communication cycle (e.g. Sent a request and received a reply).
			Yellow	Fieldbus Rx
				Flashes to indicate data bits are being received from the connected field devices.
			Yellow	Fieldbus Tx
				Flashes to indicate data bits are being sent to the connected field devices.
				Data Transfer
			Green	Indicates data is being transferred on the LAN interface.
			Yellow	Indicates data is being transferred on the USB interface.
			Green	Linked
			Yellow	USB active (for future enhancements)
				When lit the connected USB device has been detected and is in use. Do not remove
				the device while this LED is lit.
			Yellow	Service
				Indicates a Service operation is currently active (e.g. during HART tunnelling).

Additional elements in the terminal compartment

Symbol				Meaning	Remarks
				Endress+Hauser CDI port	Not used in the Tankvision instrument.
				Display port	For the connection of the local display in the housing cover.
					Is connected on delivery.
				USB port	Reserved for future enhancements.
	W&M			Weights & Measures Switch	•	:W&M parameters are unlocked and can be changed.
					•	:W&M parameters are locked and cannot be changed.

14	Endress+Hauser