Emerson 56WM WirelessHART SensEnable User manual

Reference Manual
Rev 4.0
December 2017
56WM WirelessHART®Power Meter
SensEnable™

Reference Manual December 2017
56WM WirelessHART Power Meter
56WM Revision 001
HART® Device Revision 1.0
Device Description Revision (DD) 1.0
NOTICE
This manual contains personal and system safety information.
To reduce the risk of serious injury or death due to electric shock, arc flash, fire, or explosion, before
installing, maintaining, or using this product, read the Important Safety Information and the other
sections of this manual relevant to your task.
Read this manual before working with the product. For personal and system safety, and for optimum product
performance, make sure to thoroughly understand the contents before installing, using, or maintaining this
product.
For technical assistance, call:
United States:
419-525-8307
Asia Pacific:
91-22-66620414
Europe and Latin America:
[phone]
WARNING! HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
▪This product must only be installed or serviced by qualified electricians following safe electrical work
practices.
▪Installers and servicers of this device are responsible for conformance to all applicable codes, including
NFPA 70E in the USA, and local codes.
▪Installers and servicers are responsible to confirm, with an appropriately rated voltage sensing device,
that all power has been removed prior to installing or servicing this device.
▪This product must be installed inside a suitable fire and electrically rated enclosure.
▪Do not install this device in a hazardous or classified location.
This device complies with Part 15 of the FCC Rules. Operation is subject to the following conditions:
▪This device may not cause harmful interference.
▪This device must accept any interference received, including interference that may cause undesired
operations.
▪This device must be installed to ensure a minimum antenna separation distance of 20 cm from all persons.

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Contents
Section 1 Introduction................................................................................................................................ 4
1.1 Using this Manual........................................................................................................................ 4
1.2 Product recycling/disposal......................................................................................................... 4
1.3 Glossary........................................................................................................................................ 4
Section 2 Configuration.............................................................................................................................. 5
2.1 Overview ...................................................................................................................................... 5
2.2 Safety............................................................................................................................................ 5
2.3 Device Connections .................................................................................................................... 6
2.3.1 Voltage Connections .......................................................................................................... 6
2.3.2 Current Transformer Connections .................................................................................... 7
2.3.3 Field Communication Connections................................................................................... 8
2.4 Bench Top Configuration ........................................................................................................... 8
2.4.1 Field Communicator ........................................................................................................... 8
2.4.2 AMS Device Manager.......................................................................................................... 9
2.4.3 Smart Wireless Gateway .................................................................................................... 9
2.4.4 Default Settings................................................................................................................... 9
2.5 Device Setup.............................................................................................................................. 10
2.5.1 Join Device to Network.....................................................................................................10
2.5.2 Wireless Parameters .........................................................................................................11
2.5.3 Update Rate and Device Variables .................................................................................. 11
2.5.4 Current Transformer Settings.......................................................................................... 15
2.5.5 Demand Window .............................................................................................................. 15
2.5.6 Data Scalar ......................................................................................................................... 15
2.5.7 Scaled Variables................................................................................................................. 17
2.5.8 Filtered Variables...............................................................................................................17
2.5.9 Application Alarms............................................................................................................18
Section 3 Installation ................................................................................................................................ 20
3.1 Overview ....................................................................................................................................20
3.2 Safety.......................................................................................................................................... 20
3.3 Wireless Considerations...........................................................................................................21
3.3.1 Power Up Sequence.......................................................................................................... 21
3.3.2 Antenna Position...............................................................................................................21
3.4 Physical Installation .................................................................................................................. 22
3.4.1 Mounting Enclosure..........................................................................................................22
3.4.2 Electrical Connections ...................................................................................................... 22
Section 4 Verification................................................................................................................................ 27
4.1 Overview ....................................................................................................................................27
4.2 Safety.......................................................................................................................................... 27
4.3 Verify Operation........................................................................................................................28
4.3.1 56WM................................................................................................................................. 28
4.3.2 Field Communicator ......................................................................................................... 29
4.3.3 Gateway ............................................................................................................................. 29
4.3.4 AMS..................................................................................................................................... 29
Section 5 Troubleshooting....................................................................................................................... 30
5.1 Overview ....................................................................................................................................30

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5.2 Safety.......................................................................................................................................... 30
5.3 Device Status ............................................................................................................................. 31
5.4 Wireless Network......................................................................................................................32
5.5 Application Alarms....................................................................................................................33
Section 6 Specifications............................................................................................................................ 36
6.1 Specifications ............................................................................................................................ 36
6.2 Dimensional Drawings ............................................................................................................. 37
Section 7 Product Certifications.............................................................................................................. 39
7.1 FCC/IC......................................................................................................................................... 39
7.2 Telecommunications................................................................................................................ 39
7.3 EU................................................................................................................................................ 39
7.4 ANSI ............................................................................................................................................40
7.5 UL ................................................................................................................................................ 40
Section 8 Non-DD Based Integration ...................................................................................................... 41
8.1 Alert Message Mapping............................................................................................................ 41
Tables
Table 2-1 - Default Variable Mapping ..................................................................................................... 12
Table 2-2 - Device Variables.....................................................................................................................13
Table 2-3 - Current Transformer Maximum Amperage ........................................................................ 15
Table 2-4 - Data Scalars and Values......................................................................................................... 15
Table 2-5 - Minimum Data Scalar Settings ............................................................................................. 16
Table 2-6 - General Voltage Tolerance.................................................................................................... 19
Table 4-1 - PhaseChek™ LED Table..........................................................................................................28
Table 5-1 - 56WM Device Status Information........................................................................................ 31
Table 5-2 - Wireless Troubleshooting .....................................................................................................32
Table 5-3 - 56WM Application Alarms (See section 2.5.9 Application Alarms of this manual for more information)......33
Table 8-1 - Failure Alerts........................................................................................................................... 41
Table 8-2 - Maintenance Alerts................................................................................................................41
Table 8-3 - Advisory Alerts........................................................................................................................42
Table 8-4 - Application Alerts................................................................................................................... 42

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Figures
Figure 2-1 –Voltage Connections............................................................................................................. 6
Figure 2-2 - Hinged Core Current Transformer Connections ................................................................. 7
Figure 2-3 - Rogowski Coil Current Transformer Connections............................................................... 7
Figure 2-4 - Field Communication Connections ...................................................................................... 8
Figure 2-5 - Smart Wireless Gateway Network Settings Page.............................................................. 10
Figure 2-6 - Data Capture and Processing .............................................................................................. 14
Figure 2-7 - Filter #1 Diagram .................................................................................................................. 17
Figure 2-8 - Filter #2 Diagram .................................................................................................................. 17
Figure 2-9 - Filtering Example .................................................................................................................. 18
Figure 3-1 - Antenna Position .................................................................................................................. 21
Figure 3-2 - Voltage Connection with Fused Disconnect......................................................................22
Figure 3-3 - Voltage Connection with Customer Provided Circuit Breaker ........................................ 23
Figure 3-4 - Three-Phase, Four-Wire ....................................................................................................... 24
Figure 3-5 - Three-Phase, Three-Wire..................................................................................................... 24
Figure 3-6 - Single-Phase, Three-Wire ....................................................................................................25
Figure 3-7 - Single-Phase, Two-Wire....................................................................................................... 25
Figure 4-1 - Smart Wireless Gateway Devices Page .............................................................................. 29
Figure 6-1 - Dimension are shown in INCHES (mm) ..............................................................................37
Figure 6-2 - Dimension are shown in INCHES (mm) ..............................................................................37
Figure 6-3 - Dimension are shown in INCHES (mm) ..............................................................................38

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Section 1 Introduction
1.1 Using this Manual
The sections in this manual provide information on installing, operating, and maintaining the
Emerson 56WM WirelessHART Power Meter. The sections are organized as follows:
Section 2: Configuration provides instruction on commissioning and operating the 56WM.
Information on commissioning, configuration parameters, and device variables is also included.
Section 3: Installation contains mechanical and electrical installation instructions.
Section 4: Verification contains techniques for verifying proper configuration and installation.
Section 5: Troubleshooting contains troubleshooting tips
Section 6 Appendix A: Specifications supplies reference and specification data, as well as ordering
information.
Section 7 Appendix B: Product Certifications contains agency approval information.
Section 8 Appendix C: Non-Device Description (DD) Based Integration contains both alert and device
variable information for the 56WM
1.2 Product recycling/disposal
Recycling of equipment and packaging should be taken into consideration and disposed of in
accordance with local and national legislation/regulations.
1.3 Glossary
▪56WM: 56WM WirelessHART Power Meter
▪CT: Current Transformer
▪PT: Potential (Voltage) Transformer
▪FCC: Federal Communications Commission
▪UL: Underwriters Laboratories
▪CE: Conformity European
▪IEC: International Electro-Technical Commission
▪NIST: National Institute of Standards and Technology
▪HART: Highway Addressable Remote Transducer Protocol
▪RF: Radio Frequency
▪RMS: Root Mean Square
▪AVG: Average
▪L-to-N: Line-to-Neutral
▪L-to-L: Line-to-Line (Phase)
▪PF: Power Factor
▪DV: Device Variable

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Section 2 Configuration
2.1 Overview
This section contains information on configuration that should be performed prior to installation.
Field Communicator and AMS Device Manager instructions are given to perform configuration
functions.
2.2 Safety
Instructions and procedures in this section may require special precautions to ensure the safety of
the personnel performing the operations. Information that potentially raises safety issues is
indicated by a warning symbol (⚠). Refer to the following safety messages before performing an
operation preceded by this symbol.
WARNING! HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH
▪This product must only be installed or serviced by qualified electricians following safe electrical work
practices.
▪Installers and servicers of this device are responsible for conformance to all applicable codes, including
NFPA 70E in the USA, and local codes.
▪Installers and servicers are responsible to confirm, with an appropriately rated voltage sensing device,
that all power has been removed prior to installing or servicing this device.
▪This product must be installed inside a suitable fire and electrically rated enclosure.
▪Do not install this device in a hazardous or classified location.
This device complies with Part 15 of the FCC Rules. Operation is subject to the following conditions:
▪This device may not cause harmful interference.
▪This device must accept any interference received, including interference that may cause undesired
operations.
▪This device must be installed to ensure a minimum antenna separation distance of 20 cm from all persons.

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2.3 Device Connections
The 56WM is compatible with shunted current transformers with a 0.333V output only. Serious
shock hazard and device damage may occur if unshunted current transformers are used.
When making connections with stranded wire, use ferrules on all terminal block sensor connections.
2.3.1 Voltage Connections
Connect the voltage phase conductors L1, L2, L3, N as necessary to the 56WM. The minimum
conductor is 14 AWG, THHN, 600VAC. The neutral connection on the 56WM must always be
connected to either the neutral or ground conductor of the load to ensure accurate measurements.
See Figure 2-1.
Figure 2-1 –Voltage Connections

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2.3.2 Current Transformer Connections
Connect the current transformer conductors so that the phase conductor for CT1 is the same phase
conductor for voltage L1, and so on. This ensures proper phasing for accurate measurements. See
Section 3.4.2 Electrical Connections for additional information.
2.3.2.1 Hinged Core Current Transformer Connections
Connect the white wire to the positive terminal and connect the black wire to the negative terminal
on the current transformer connector. See Figure 2-2.
Figure 2-2 - Hinged Core Current Transformer Connections
2.3.2.2 Rogowski Coil Current Transformer Connections
Connect the white wire to the positive terminal, connect the brown wire to the negative terminal,
and connect the shield wire to the “S” terminal on the current transformer connector. See Figure 2-3.
Figure 2-3 - Rogowski Coil Current Transformer Connections

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2.3.3 Field Communication Connections
The 56WM must be powered by the USB connection for configuration. The USB Type B connection
may also be used for configuring the 56WM from a computer.
Connect the two 4mm banana jacks to a field communicator and the USB connector for power to
configure the 56WM. See Figure 2-4.
Figure 2-4 - Field Communication Connections
2.4 Bench Top Configuration
Bench top configuration consists of testing the 56WM and verifying its configuration data. The
56WM must be configured prior to installation, which may be performed either directly or remotely.
Direct configuration can be performed using a Field Communicator, AMS Device Manager, or any
WirelessHART® Communicator. Remote configuration can be performed using AMS Device
Manager, or the Smart Wireless Gateway.
The 56WM must be powered by the USB connection for configuration. To configure the 56WM,
connect a field communicator to the field communication connectors.
2.4.1 Field Communicator
When performing device configuration directly, verify that the 56WM is powered on and turn on the
field communicator by pressing the POWER key. When using a field communicator, any
configuration changes must be sent to the 56WM by using the Send key.
The field communicator will search for a HART-compatible device and indicate when the connection
was made. If the field communicator fails to connect, it will indicate that no device was found. If this
occurs, refer to the Troubleshooting of this document.
Note
For HART communication via a field communicator, a 56WM Device Description (DD) is required. To
obtain the latest DD, visit the 475 Field Communicator System Software and Device Description site
at: http://tinyurl.com/475fieldcommunicator.
Field Communicator (4mm Banana Jacks)
USB Type B

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2.4.2 AMS Device Manager
When configuring the 56WM using AMS Device Manager or AMS Wireless Configurator, double click
the 56WM device icon (or right click and select Configure/Setup), then select the Configure/Setup
tab. AMS Device Manager configuration changes are implemented when the Apply button is
selected.
Note
For HART communication via AMS, a 56WM Device Description (DD) is required. To obtain the latest
DD, visit the Emerson site at: http://tinyurl.com/56WMdevicedescription.
2.4.3 Smart Wireless Gateway
The 56WM supports limited remote configuration through the Smart Wireless Gateway. The
Gateway allows configuration of the following device parameters: HART Tag (long tag), Short Tag,
Descriptor, and Update Rate.
2.4.4 Default Settings
Unless specified with the Site Assessment Form, the 56WM default configuration is shown below:
HART Tag (long tag)
blank
Short Tag
56WM
Descriptor
T-O-D
Network ID
1111
Join Key
11111111 00000000 00000000 00000000
Update Rate
1 minute
Device Variables
See Update Rate and Device Variables Section

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2.5 Device Setup
All parameters/settings for the 56WM discussed in the device setup may be changed during field
configuration, or at any time via AMS Device Manager or Field Communicator.
2.5.1 Join Device to Network
To communicate with the Smart Wireless Gateway, and ultimately the host system, the 56WM must
be configured to communicate over the wireless network.
Using a field communicator or AMS Device Manager to communicate to the 56MW, enter the
Network ID and Join Key so they match the Network ID and Join Key of the Smart Wireless Gateway
and the other devices in the network. If the Network ID and Join Key are not identical to those set in
the Gateway, the 56WM will not communicate with the network. The Network ID may be obtained
from the Smart Wireless Gateway on the System Settings>Network>Network Settings page of the
Smart Wireless Gateway web based user interface. See Figure 2-5.
Figure 2-5 - Smart Wireless Gateway Network Settings Page

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2.5.2 Wireless Parameters
The following parameters can be configured either directly with a field communicator or remotely
with a HART host.
▪HART Tag (Long Tag): 32 Characters Maximum
▪Short Tag: 8 Characters Maximum
▪Descriptor: 16 Characters Maximum
▪Message: 32 Characters Maximum
▪Date: DD/MM/YYYY
2.5.3 Update Rate and Device Variables
The update rate is the frequency at which a measurement is transmitted over the wireless network.
This by default is one minute. This may be changed during field configuration, or at any time via AMS
Device Manager. The update is user selectable from one second to 60 minutes. Each burst message
can have an unique update rate.
The 56WM transmits five burst messages with 39 device variables (DV) by default. The default device
variables are shown in Table 2-1.

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Table 2-1 - Default Variable Mapping
Burst Message 0
Burst Message 2
Slot
DV
Description
Slot
DV
Description
Slot 0
9
L1-L2 Voltage AVG
Slot 0
25
L3-L1 Voltage AVG
Slot 1
10
L1 Amperage AVG
Slot 1
26
L3 Amperage AVG
Slot 2
5
kW System AVG
Slot 2
27
L3 kW AVG
Slot 3
6
kWh System
Slot 3
28
L3 kWh
Slot 4
3
Voltage Line-Line System
Slot 4
29
L3 kVA AVG
Slot 5
4
Amperage System
Slot 5
30
L3 kVAR AVG
Slot 6
34
Line Frequency AVG
Slot 6
31
L3 Displacement PF AVG
Slot 7
250
Not Used
Slot 7
32
L3 Apparent PF AVG
Burst Message 1
Burst Message 3
Slot
DV
Description
Slot
DV
Description
Slot 0
17
L2-L3 Voltage AVG
Slot 0
11
L1 kW AVG
Slot 1
18
L2 Amperage AVG
Slot 1
12
L1 kWh
Slot 2
19
L2 kW AVG
Slot 2
13
L1 kVA AVG
Slot 3
20
L2 kWh
Slot 3
14
L1 kVAR AVG
Slot 4
21
L2 kVA AVG
Slot 4
15
L1 Displacement PF AVG
Slot 5
22
L2 kVAR AVG
Slot 5
16
L1 Apparent PF AVG
Slot 6
23
L2 Displacement PF AVG
Slot 6
33
Voltage Line-Neutral System
Slot 7
24
L2 Apparent PF AVG
Slot 7
1
Onboard Temperature
Burst Message 4
Slot
DV
Description
Slot 0
35
kW System Max
Slot 1
36
kW System Min
Slot 2
37
kW System Demand Max
Slot 3
38
kW System Demand Min
Slot 4
0
Sensor Type
Slot 5
7
kVAh System
Slot 6
8
kVARh System
Slot 7
2
Onboard Bus Voltage
The default device variable map and update rate can be changed during field configuration, or at any
time via AMS Device Manager or Field Communicator. The update rate can be unique for each burst
message. Available device variables are shown below:

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Table 2-2 - Device Variables
Instantaneous and Power Variables
Averaged Variables
Description
DV
Description
DV
Voltage Line to Line System
3
Voltage L1 to L2 AVG
9
Amperage System
4
Voltage L2 to L3 AVG
17
Voltage Line to Neutral System
33
Voltage L1 to L3 AVG
25
kW System Max
35
Voltage L1 to Neutral AVG
44
kW System Min
36
Voltage L2 to Neutral AVG
45
kW Demand System Max
37
Voltage L3 to Neutral AVG
46
KW Demand System Min
38
Amperage L1 AVG
10
KW Demand System AVG
39
Amperage L2 AVG
18
Amperage L3 AVG
26
Line Frequency AVG
34
Energy Variables
Displacement PF L1 AVG
15
Description
DV
Displacement PF L2 AVG
23
kWh system
6
Displacement PF L3 AVG
31
kVAh System
7
Apparent PF L1 AVG
16
kVARh System
8
Apparent PF L2 AVG
24
kWh L1
12
Apparent PF L3 AVG
32
kWh L2
20
Displacement PF System AVG
42
kWh L3
28
Apparent PF System AVG
43
kVARh L1
48
kW system AVG
5
kVARh L2
50
kVA System AVG
40
kVARh L3
52
kVAR System AVG
41
kVAh L1
47
kW L1 AVG
11
kVAh L2
49
kW L2 AVG
19
kVAh L3
51
kW L3 AVG
27
kVA L1 AVG
13
kVA L2 AVG
21
HART Variables
kVA L3 AVG
29
Primary Variable (PV)
246
kVAR L1 AVG
14
Secondary Variable (SV)
247
kVAR L2 AVG
22
Tertiary Variable (TV)
248
kVAR L3 AVG
30
Quaternary Variable (QV)
249
THD L1
54
Battery Life
243
THD L2
55
PV Percent Range
244
THD L3
56
PV Loop Current
245
THD System
57

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When selecting device variables, the number of burst messages, and the update rate of each burst
message, consideration must be taken for the effect on the mesh network and other transmitters on
the network. Below is the maximum network size recommendation for the Smart Wireless Gateway.
The number of wireless devices assumes one burst message per device.
▪100 Wireless Devices each with an 8 second update rate
▪50 Wireless Devices each with a 4 second update rate
▪25 Wireless Devices each with a 2 second update rate
▪12 Wireless Devices each with a 1 second update rate
For a mesh network with only 56WM’s each configured with five burst messages, the approximate
network size is shown below.
▪20 Wireless Devices each with an 8 second update rate
▪10 Wireless Devices each with a 4 second update rate
▪5 Wireless Devices each with a 2 second update rate
▪3 Wireless Devices each with a 1 second update rate
If possible, each 56WM should be installed so that it can wirelessly transmit directly with the
Gateway. This will help to reduce the network load on battery powered transmitters in that mesh
network. The network manager may adjust the network paths to maximize data reliability.
When the 56WM is commissioned with a DeltaV system, DeltaV requires the HART variable PV Loop
Current. It is recommended to only use Burst Message 0 and Burst Message 1. PV Loop Current
should be mapped to a slot in Burst Message 1. All other burst messages should be turned off. This
will minimize unnecessary network traffic and maximize the number of device variables available to
the DeltaV system. In addition, it is recommended to map system device variables (i.e., Voltage Line-
to-Line System, Amperage System, etc.) to PV, SV, TV, QV since DeltaV requests these HART
variables. If the DeltaV system is utilizing Modbus to obtain device variables, additional burst
messages may be turned on.
A simplified diagram of the data capture and processing of the 56WM is shown below.
Figure 2-6 - Data Capture and Processing
Analog to Digital
Converter, 12kHz
Sampling Data Scalar Filter
Simple Moving
Average Filter #1
Simple Moving
Average Filter #2
Instantaneous
Device Variables
Averaged Device
Variables
WirelessHART
Radio
Energy Device
Variables
Power Meter Processor
WirelessHART Processor
Single Waveform
Capture Every 500ms
Modbus Communication
Every 1 sec
Wireless Update Rate,
1 minute default
Electrical Load
Device Variable
Scaling

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2.5.4 Current Transformer Settings
The 56WM must be configured to match the current transformers that are connected to it for each
application. There are two current transformer types:
CT Type
1. Millivolt CT (Hinged Core CT’s)
2. RoCoil (Rogowski Coil CT’s)
The CT Amps must be configured to match the CT amperage listed on the CT label for all hinged
core CT’s. The CT Amps setting does not need to be configured for Rogowski Coils, simply select
Rogowski Coil. See Table 2-3.
Table 2-3 - Current Transformer Maximum Amperage
Current
Transformer
CT Max
Amperage
CT-SRS-005
5A
CT-SRS-050
50A
CT-SRL-100
100A
CT-SRL-200
200A
CT-SRL-400
400A
2.5.5 Demand Window
The 56WM can provide power demand calculations that may be used for utility billing. The default
demand window is 15 minutes and is configurable from 1 to 60 minutes. The 56WM can provide
maximum and averaged power values over the specified demand window.
2.5.6 Data Scalar
Internally, the 56WM processor uses a data scaling feature to maximize the dynamic range of the
measured data. Measurements that can be scaled include volts, amps, power factor, power, and
energy. The maximum decimal value of the measurements must be scaled to fit within the range of
0 to 65,535. See Table 2-4.
Table 2-4 - Data Scalars and Values
Data Scalar
Scalar Value
Volts
Amps
Power
Factor
Power
(kW, kVAR, kVA)
Energy
(kWh, kVARh,
kVAh)
0
0.1
0.01
0.01
0.00001
0.00001
1
0.1
0.1
0.01
0.001
0.001
2
0.1
0.1
0.01
0.01
0.01
3
0.1
0.1
0.01
0.1
0.1
4
1.0
1.0
0.01
1.0
1.0
5
1.0
1.0
0.01
10
10
≥6
1.0
1.0
0.01
100
100

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The table below are the minimum recommended scalar settings based on current transformer size.
Table 2-5 - Minimum Data Scalar Settings
Current Transformer
Size or Max Amperage
3-Phase System Voltage
240 Volts
480 Volts
50
Data Scalar = 1
Data Scalar = 2
100
Data Scalar = 2
Data Scalar = 2
200
Data Scalar = 2
Data Scalar = 2
400
Data Scalar = 2
Data Scalar = 2
600
Data Scalar = 2
Data Scalar = 3
1000
Data Scalar = 3
Data Scalar = 3
3000
Data Scalar = 3
Data Scalar = 3
To determine the appropriate data scalar for an application, use the following formula:
Measured or Calculated Values / Data Scalar Value ≤ 65,535 (Register Value)
If the data scalar is too low, the data may be inaccurate. If the data scalar is too high, the significant
digits after the decimal are removed. Below is an example of how to calculate the appropriate data
scalar.
Example 1:
▪Voltage = 480V
▪Amperage = 100A
▪Total System Power = (480V) * (100A) * 3 = 144kW
▪Select Data Scalar = 2, therefore data scalar value is 0.01
▪Register Value = 144kW / 0.01 = 14,400
▪Check 14,400 ≤ 65,535: Yes this data scalar is correct.
Example 2:
▪Voltage = 480V
▪Amperage = 1000A
▪Total System Power = (480V) * (1000A) * 3 = 1,440kW
▪Select Data Scalar = 1, therefore data scalar value is 0.001
▪Register Value = 1,440kW / 0.001 = 1,440,000
▪Check 1,440,000 ≤ 65,535: No this data scalar is incorrect.
▪Change the data scalar value and check result again.

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2.5.7 Scaled Variables
The 56WM can scale the measured values for voltage, current, power, and energy. The 56WM can
be configured with a voltage scalar value and/or a current scalar value. The 56WM calculates the
appropriate power and energy scalar values from the user defined voltage and current scale values.
For example, in a medium voltage application where the primary voltage of 4.16kV is stepped down
with a 10:1 potential transformer to 416V, the 56WM would be configured with a voltage scale of 10.
2.5.8 Filtered Variables
The 56WM has two filters that can be configured to average the measured data. Both filters can filter
specific device variable using a simple moving average algorithm. The simple moving average
formula is shown below.
   󰇛󰇜
 


The number of samples, n, can be configured from 1 to 50. The default value for the number of
samples to filter is 1. To turn off the filter, set the number of samples to 1. Simplified diagrams of the
filters are shown in Figure 2-7 and Figure 2-8.
Figure 2-7 - Filter #1 Diagram




1
0
1n
i
imp
n
Raw Data
Every 1 sec
Filter #1
Filter #1
Device Variable
(Voltage, Amperage,
Power, Power Factor)
1 ≤ n≤ 50,
Default n=1
Figure 2-8 - Filter #2 Diagram




1
0
1n
i
imp
n
Raw Data
Every 1 sec
Filter #1
Filter #2
Device Variable
(Voltage, Amperage,
Power, Power Factor)




1
0
1n
i
imp
n
Filter #2
1 ≤ n≤ 50,
Default n=1
1 ≤ n≤ 50,
Default n=1
The 56WM is a waveform single cycle sampling meter. It samples one cycle of a waveform at 12kHz.
It takes this measurement every half second. It measures voltage, current, frequency, and phase
angle to compute power factor, power, and energy. The filtered variables are shown in Table 2-2,
“Averaged Variables”. The default value for the number of samples to filter is 1, which means the
filter is off by default. The number of samples for each filter, n, can be configured from 1 to 50.

Reference Manual December 2017
18
Figure 2-9 below is an example of both averaging filters set to maximum.
Figure 2-9 - Filtering Example
2.5.9 Application Alarms
The 56WM has several user configurable application alarms. These alarms include, low voltage
tolerance, voltage imbalance tolerance, amperage imbalance tolerance, line frequency tolerance,
minimum power factor, and general voltage tolerance. In addition, the 56WM has a configurable
number of consecutive readings before setting the alarm. By default, these alarms are turned off.
Transition Filter (Default n = 0)
This is the number of consecutive readings before setting and clearing an application alarm. When
n=0all application alarms are turned off.
Low Voltage Tolerance (Default n= 0.8)
The low voltage tolerance checks than no line-to-neutral voltage is low when compared to the other
line-to-neutral voltages.
▪Voltage L1-N < [(Voltage L2-N*n) or (Voltage L3-N* n)]
▪Voltage L2-N < [(Voltage L1-N* n) or (Voltage L3-N* n)]
▪Voltage L3-N < [(Voltage L1-N* n) or (Voltage L2-N* n)]
0
100
200
300
400
500
600
0:00:00 0:00:43 0:01:26 0:02:10 0:02:53 0:03:36 0:04:19 0:05:02 0:05:46 0:06:29 0:07:12
Voltage
Time
56WM Filter #1 n=50, Filter #2 n=50
Input Voltage Filter #1 Filter #2