ILMU AUTOMATION

SCADA with Database always use Industrial PC for HMI. How to make backup the PC SCADA? Please read simple Tips and Tricks to make Backup PC. "It's important for your as Automation Engineer in Industries"

Making images of hard drives is a useful way of having backup copies of all your information, including your entire operative system.

For many years, only a few companies made this kind of programs and they were expensive. But now, there are some free alternatives that make this possible without spending any money. Besides, they are pushing commercial products to lower its prices because of the new competition.

The industry is lead by two applications, Acronis True Image and Norton Ghost. These two are great and include an impressive array of options that many of the free applications don’t have. But most users won’t use them anyway.

DriveImage XML

The first application i want to talk you about is DriveImage XML, from Runtime Software.

Official description:

DriveImage XML is an easy to use and reliable program for imaging and backing up partitions and logical drives.

The program allows you to:

• Backup logical drives and partitions to image files
• Browse these images, view and extract files
• Restore these images to the same or a different drive
• Copy directly from drive to drive
• Schedule automatic backups with Windows Task Scheduler

Macrium Reflect Free

The second one is Macrium Reflect Free.

Official description:

• Create a disk image whilst running Windows using Microsoft Volume Shadow copy Service (VSS).
• Image to Network, USB, FireWire drives and DVD.
• Built in scheduler.
• 32 bit and native 64 bit versions.
• Industry leading compression levels and speed.
• Linux based Rescue CD with Network access and full GUI. Only 6.5MB in size!
• Built in CD/DVD packet writing engine. Supports packet writing to DVD DL media with Windows Vista.
• HTML log files.

No Excuses

There are free tools to make those important backup disk images. It is up to you which one to choose.

 No, the EEPROM Memory Cassette does not require a battery.

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 The conditions for setting up this type of connection are as follows:

Select any of the following: C200HE-CPU11, C200HE-CPU32, or C200HE-CPU42.

 There are two main types of maintenance: corrective maintenance (i.e., inspections and replacements that are performed after a failure has occurred) and preventative maintenance (i.e., inspections and maintenance that are performed before a failure occurs).

The following items are useful for reference when determining maintenance timing.

For more datail Information please Click Here!

What points do you need to remember during the handling of micro memory cards?

Description:
This entry describes how to work with Micro
Memory Cards (MMC). A sample project is also included in Point 4. The
program shows how you can check whether specific data in a data block
is located in the load memory.

1. How should I save blocks or configuration data on the MMC which are transferred online to the CPU?

When you load blocks (OB, FC, FB, DB) and system data (from the
HW Config among other places, for example) into the CPU, they are automatically saved in such a way as to be safeguarded against voltage failure. The MMC is a flash EPROM medium.

2. Is there still need for the "Copy RAM to ROM..." function?

Not for saving blocks. However, if you have changed data blocks,
for instance if you have optimized control parameters, this function
also allows you to save the changed data values on the MMC (i.e. on the
load memory), which means that these new values are also available
following general PLC resetting (including in cases where the MMCs are
used as spare parts in another CPU).

Warning:
Please note carefully that the "Copy RAM to
ROM..." function affects all data blocks that are identified as
"unlinked". In the case of these data blocks, when the "Copy RAM to
ROM..." function is performed, the initial values in the load memory
(on the MMC) are overwritten with the actual values in the main memory.

For all data blocks, the initial values are taken as new values after
an overall reset. In the case of non-remanent data blocks the initial
values are also taken as new values after POWER OFF/ON or after
STOP/RUN operating modes.

If you want to save individual data blocks or data block
elements in the load memory, you can use SFC84 to do that. Here, please
note the following Point 3.

3. Can I save data blocks on the MMC via the user program, i.e. use the content as new initial values in the load memory?

CPUs with MMCs feature the SFCs 82, 83 and 84 for this purpose:

• SFC82 allows you to set up a data block in the load memory.
  
• SFC83 allows you to copy data areas from the load memory to the main memory, and
  
• SFC84 saves data areas in the load memory, i.e. it performs
  the function which is formulated in the question. However, bear in mind
  that the MMCs support a limited number of writing cycles (according to
  the manufacturer's details, 100,000 writing cycles are possible). For
  details about the memory concept of CPUs (load memory, main memory...
  ), please refer to the FAQ in Entry ID 7302326.

4. How can I check whether the data is really saved in the load memory with SFC84?

A check is possible if the data block is declared as "unlinked".

After copying an "unlinked" DB with SFC83 to the working area of
another DB you can make a check. In the load memory itself it is not
possible to access with a variables table or via "Monitor/control
variable", because access is made here to the working area. There is an
example of how to work with SFC83 attached. This illustrates how the
SFC 84 works.

Please also bear in mind that SFC 83 and SFC 84 work asynchronously.
This means that the SFCs might need several cycles to complete a job.

If the data block in the load memory has the attribute "unlinked", you
can make the check by loading the DB into the PG. Here, STEP 7
retrieves the current values from the load memory during each loading
process. In this regard, also refer to the FAQ in Entry ID 21688777.

Sample project:
Save the "MMC_S7_300_SFC83.zip" file
in a separate directory and then dearchive it. The S7 project then
unpacks with all the associated subdirectories. You can use the SIMATIC
Manager to open and process the extracted project.

MMC_S7_300_SFC83.zip ( 158 KB )

IMPORTANT
The sample program is freeware. Any user
can use, copy and forward this program FREE OF CHARGE. The authors and
owners of this program take no responsibility whatsoever for the
functionality and compatibility of this software. Use of the software
is at the user's own risk. Since this software is free of charge, there
is no warranty nor entitlement to error correction and hotline support.

5. When is it useful to compress an S7-300 CPU with MMC?

Deleting blocks on the CPU creates gaps in the load and main
memories. The gaps are not automatically closed when new or changed
blocks are transferred. When you compress, the gaps are closed by
copying the existing or new blocks. The procedure is comparable with
the defragmenting of hard disks in Windows.
You reduce cycle times
by compressing. That is why it is only useful to compress in order to
close a large number of gaps after blocks have been deleted frequently
in the CPU.

Compressing just after performing the "Load user program onto memory card" function is not
useful, because the MMC is deleted when the function is performed and
the blocks can be transferred without any gaps onto the MMC.

Warning:
Compressing, transferring and deleting blocks extends the cycle time of the CPU.

In the STOP operating mode you can perform compressing completely. In
the RUN-P operating mode, blocks that are open because of the running
program cannot be moved when compressing is performed.

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Which memory cards can you use with a S7-300 CPU?

Description:
The following tables (Table 01 to Table 08) show the S7-300 CPUs and the memory cards to be used with them.
Here we distinguish between:

• MC (Memory Card)
• MMC (Micro Memory Card)

CPU 312	Order no.	Type of Memory Card
CPU 312	6ES7 312-1AD10-0AB0	MMC  max. 4MB
	6ES 7 312-1AE13-0AB0	MMC  max. 4MB
CPU 312C	6ES7 312-5BD00-0AB0	MMC  max. 4MB
	6ES7 312-5BD01-0AB0	MMC  max. 4MB
	6ES7 312-5BE03-0AB0	MMC  max. 4MB
CPU 312 IFM	6ES7 312-5AC02-0AB0	No Memory Card
	6ES7 312-5AC82-0AB0	No Memory Card

Table 01
 

CPU 313	Order no.	Type of Memory Card
CPU 313	6ES7 313-1AD02-0AB0	MC  max. 512KB
	6ES7 313-1AD03-0AB0	MC  max. 4MB
CPU 313C	6ES7 313-5BE00-0AB0	MMC  max. 4MB
	6ES7 313-5BE01-0AB0	MMC  max. 8MB
	6ES7 313-5BF03-0AB0	MMC  max. 8MB
CPU 313C-2 DP	6ES7 313-6CE00-0AB0	MMC  max. 4MB
	6ES7 313-6CE01-0AB0	MMC  max. 8MB
	6ES7 313-6CF03-0AB0	MMC  max. 8MB
CPU 313C-2 PtP	6ES7 313-6BE00-0AB0	MMC  max. 4MB
	6ES7 313-6BE01-0AB0	MMC  max. 8MB
	6ES7 313-6BF03-0AB0	MMC  max. 8MB

Table 02
 

CPU 314	Order no.	Type of Memory Card
CPU 314	6ES7 314-1AE03-0AB0	MC  max. 512KB
	6ES7 314-1AE04-0AB0	MC  max. 4MB
	6ES7 314-1AE83-0AB0	MC  max. 512KB
	6ES7 314-1AE84-0AB0	MC  max. 4MB
	6ES7 314-1AF10-0AB0	MMC  max. 8MB
	6ES7 314-1AF11-0AB0	MMC  max. 8MB
	6ES7 314-1AG13-0AB0	MMC  max. 8MB
	6ES7 314-5AE03-0AB0	No Memory Card
	6ES7 314-5AE10-0AB0	MC  max. 4MB
	6ES7 314-5AE83-0AB0	No Memory Card
CPU 314C-2 DP	6ES7 314-6CF00-0AB0	MMC  max. 4MB
	6ES7 314-6CF01-0AB0	MMC  max. 8MB
	6ES7 314-6CF02-0AB0	MMC  max. 8MB
	6ES7 314-6CG03-0AB0	MMC  max. 8MB
CPU 314C-2 PtP	6ES7 314-6BF00-0AB0	MMC  max. 4MB
	6ES7 314-6BF01-0AB0	MMC  max. 8MB
	6ES7 314-6BF02-0AB0	MMC  max. 8MB
	6ES7 314-6BG03-0AB0	MMC  max. 8MB

Table 03
 

CPU 315	Order no.	Type of Memory Card
CPU 315	6ES7315-1AF02-0AB0	MC  max. 512KB
	6ES7 315-1AF03-0AB0	MC  max. 4MB
CPU 315-2 DP	6ES7 315-2AF02-0AB0	MC  max. 512KB
	6ES7 315-2AF03-0AB0	MC  max. 4MB
	6ES7 315-2AF82-0AB0	MC  max. 512KB
	6ES7 315-2AF83-0AB0	MC  max. 4MB
	6ES7 315-2AG10-0AB0	MMC  max. 8MB
CPU 315-2 PN/DP	6ES7 315-2EG10-0AB0	MMC  max. 8MB
	6ES7 315-2EH13-0AB0	MMC  max. 8MB
CPU 315F-2 DP	6ES7 315-6FF01-0AB0	MMC  max. 8MB
CPU 315F-2 PN/DP	6ES7 315-2FH10-0AB0	MMC  max. 8MB
	6ES7315-2FH13-0AB0	MMC  max. 8MB
CPU 315T-2 DP	6ES7 315-6TG10-0AB0	MMC  min. 4MB, max. 8MB
	6ES7 315-6TH13-0AB0	MMC  min. 4MB, max. 8MB

Table 04
 

CPU 316	Order no.	Type of Memory Card
CPU 316	6ES7 316-1AG00-0AB0	MC  max. 512KB
CPU 316-2DP	6ES7 316-2AG00-0AB0	MC  max. 4MB

Table 05
 

CPU 317	Order no.	Type of Memory Card
CPU 317-2 DP	6ES7 317-2AJ10-0AB0	MMC  max. 8MB
CPU 317-2 PN/DP	6ES7 317-2EJ10-0AB0	MMC  max. 8MB
	6ES7 317-2EK13-0AB0	MMC  max. 8MB
CPU 317F-2 DP	6ES7 317-6FF00-0AB0	MMC  max. 8MB
	6ES7 317-6FF03-0AB0	MMC  max. 8MB
CPU 317F-2 PN/DP	6ES7 317-2FJ10-0AB0	MMC  max. 8MB
	6ES7 317-2FK13-0AB0	MMC  max. 8MB
CPU 317T-2 DP	6ES7 317-6TJ10-0AB0	MMC  min. 4MB, max. 8MB
	6ES7 317-6TK13-0AB0	MMC  min. 4MB, max. 8MB

Table 06
 

CPU 318	Order no.	Type of Memory Card
CPU 318-2	6ES7 318-2AJ00-0AB0	MC  max. 4MB

Table 07

If you are doing an update of the operating system for the S7-318-2 CPU, you can use S7-400 memory cards, order number 6ES7952-1K... For details, please see Entry ID: 7286150.
 

CPU 319	Order no.	Type of Memory Card
CPU 319-3 PN/DP	6ES7 318-3EL00-0AB0	MMC  max. 8MB
CPU 319F-3 PN/DP	6ES7 318-3FL00-0AB0	MMC  max. 8MB

Table 08

List of Memory Cards (MC):
In normal mode, only the "short" memory cards (MC) can be used with S7-300 CPUs (with MC slot). Table 09 lists the order numbers of these memory cards.
 

Designation	Order no.
Memory Card FEPROM 16 KB	6ES7 951-0KD00-0AA0
Memory Card FEPROM 32 KB	6ES7 951-0KE00-0AA0
Memory Card FEPROM 64 KB	6ES7 951-0KF00-0AA0
Memory Card FEPROM 128 KB	6ES7 951-0KG00-0AA0
Memory Card FEPROM 256 KB	6ES7 951-1KH00-0AA0
Memory Card FEPROM 512 KB	6ES7 951-0KJ00-0AA0
Memory Card FEPROM 1 MB	6ES7 951-1KK00-0AA0
Memory Card FEPROM 2 MB	6ES7 951-1KL00-0AA0
Memory Card FEPROM 4 MB	6ES7 951-1KM00-0AA0
Memory Card FEPROM 16 KB*	6ES7 951-0KD80-0AA0
Memory Card FEPROM 32 KB*	6ES7 951-0KE80-0AA0
Memory Card FEPROM 64 KB*	6ES7 951-0KF80-0AA0
Memory Card RAM 128 KB	6ES7 951-0AG00-0AA0
Memory Card RAM 256 KB	6ES7 951-1AH00-0AA0
Memory Card RAM 512 KB	6ES7 951-1AJ00-0AA0
Memory Card RAM 1 MB	6ES7 951-1AK00-0AA0
Memory Card RAM 2 MB	6ES7 951-1AL00-0AA0

Table 09
* These memory cards are designed for use in the extended temperature range.

More information is available in the manual "SIMATIC Automation System S7-300, CPU Data, CPUs 312IFM to 318-2 DP", sections 1.1.4 and 4.2 in Entry ID: 8860591.

List of Micro Memory Cards (MMC):
Table 10 lists the order numbers of the Micro Memory Cards (MMC).
 

Designation	Order no.
Micro Memory Card 64 KB	6ES7 953-8LF20-0AA0
Micro Memory Card 128 KB	6ES7 953-8LG11-0AA0
Micro Memory Card 512 KB	6ES7 953-8LJ20-0AA0
Micro Memory Card 2 MB	6ES7 953-8LL20-0AA0
Micro Memory Card 4 MB	6ES7 953-8LM20-0AA0
Micro Memory Card 8 MB	6ES7 953-8LP20-0AA0

Table 10

QUESTION:
The analog values are transferred only in part or not at all. How can I clear this problem?

ANSWER:
If none or only part of the analog values are transferred, or the transferred values are incorrect, then this might have something to do with the length of the consistent data of the slave (affects S7-300/400 CPUs).
If more than 4 bytes (or exactly 3 bytes) are consistent over the entire length, then you must access the analog values of the slave with the SFCs 14 "DPRD_DAT" and 15 "DPWR_DAT". A description of the SFCs is given in the manual "System Software for S7-300/400 System and Standard Functions". The information on consistent data lengths of the PROFIBUS DP slave are given in the HW Config.
Procedure:

1. In the HW Config you mark the PROFIBUS slave.

2. Double-click the module from which you want to know which consistent areas it has. In the "Address/ID" tab of the "Properties - DP slave" window you can see the length over which the data is consistent.

Instructions:
In order to reduce configuration work, parts of a project are often copied and inserted into a new project.
Here, tags and objects are copied, which are no longer used in the newly created project.

WinCC flexible provides a function which can be used to have these unused tags displayed.

In the "Edit" menu you select the command "Find in project...". In the window that opens you select the required search options.

For example, to find unused tags you select the "Filter" item. In the text list you select "Tag" as the object type.
Under the "In" item you specify the folder in which the search for the object type is to be made. This is particularly useful when there are multiple operator panels in the project.

Under "Reference" you select the subitem "Not used by" -> "All types". Then click the "Find now" button.

Now on the right you get a display of all the unused tags.
To delete them you select the tags concerned and right-click. A pop-up menu opens in which you select "Delete" to delete the marked tags.

( 37 KB )
Fig. 01

Keywords:
Delete tags

QUESTION:  
Can I copy a SIMATIC WinCC flexible project integrated in SIMATIC STEP 7 at file level? 

ANSWER:  
Copying of HMI projects integrated in STEP 7 at file level (e.g. with Windows Explorer via Copy/Cut and Paste) is not possible in combination with WinCC flexible. 

By copying of HMI projects integrated in STEP 7 (*.hmi) at file level you lose internal references from the WinCC flexible project to the the associated STEP 7 project. Then synchronization between the WinCC flexible project and the STEP 7 project is no longer possible.

When you attempt to open an HMI station copied at file level from the SIMATIC Manager, you get a message regarding access to STEP 7 information after opening the HMI station in WinCC flexible ES.

1. Proceed as follows if you want to copy a SIMATIC HMI station from a STEP 7 project:

• Open the STEP 7 concerned with the SIMATIC Manager.
  
  
• Start WinCC flexible via "SIMATIC HMI Station > Right-click on WinCC flexible RT > Open object".
  
  
• In WinCC flexible you select the menu "Project > Copy from STEP 7" to create a non-integrated HMI project from the SIMATIC HMI station.
  
  Note: 
  The original SIMATIC HMI station or the HMI project is retained in the STEP 7 project. 

Fig. 1: Creating a non-integrated HMI project

• You can then handle the HMI project created just like a normal HMI project.
   

2. Proceed as follows if you want to integrate back into STEP 7 a SIMATIC HMI station copied from a STEP 7 project:

• Open the HMI project concerned with WinCC flexible.
   
• In the menu "Project > Integrate in STEP 7" select the relevant STEP 7 project with a double-click.

Fig. 2: Integrating an HMI project

Fig. 3: Selecting the relevant STEP 7 project

• Now the HMI project not integrated in STEP 7 is integrated into the STEP 7 project selected.
  
  Note: 
  This function only inserts the operator panel located in an HMI project into a STEP 7 project. If you want to replace an existing HMI station, then the HMI station to be replaced has to be deleted in the SIMATIC Manager.
   
• After integrating the HMI station you have to check and possible modify the hardware configuration of the HMI station in the STEP 7 "HW Config" as well as the connection parameters in SIMATIC WinCC flexible via "Communication > Connections".

Keywords:
Copy, Paste, Cut, Move, File management, Integration

Project archiving and migration
If you wish to archive a WinCC flexible project, you can reduce the volume and file size significantly by archiving just the following project files. Please refer also to the notes at the end of the entry on migrating WinCC flexible projects (opening a WinCC flexible project that is based on a previous version).

No.	Project archiving in WinCC flexible 2007 and WinCC flexible 2008
1	Standalone project (a WinCC flexible project not integrated in STEP 7) Start WinCC flexible ES and archive the project via the menu command "Project > Archive...". The project to be archived must not be opened during archiving. The ZIP file created contains only the two files required for restoring your project - "Project.hmi" and "Project_log.LDF". The next time you dearchive and open the project, the files deleted previously are automatically regenerated. ( 59 KB ) Fig. 01
2	WinCC flexible integrated in STEP 7 In the case of a project integrated in STEP 7, you use the archiving method of the SIMATIC Manager (File > Archive...). From STEP 7 version V5.4 SP2 onwards, the WinCC flexible files are automatically reduced to files required for restoring your project.  The next time you dearchive and open the project, the files deleted previously are automatically regenerated. If you are using STEP 7 V5.4 + SP1, please refer to the information on "Project archiving in WinCC flexible 2005 SP1, Point 2".

 

No.	Project archiving in WinCC flexible 2005 SP1
1	Standalone project (a WinCC flexible project not integrated in STEP 7) If just the WinCC flexible project is to be archived without information for the delta compile, then only the following files are required. ProjectName.hmi ProjectName_log.ldf The files are located in the relevant project directory. The next time you open the project, the files deleted previously are automatically regenerated. "Attachment 1" contains a breakdown of WinCC flexible files based on a sample configuration. Attachment 1: Project_Data_2005.zip ( 11 KB )
2	WinCC flexible integrated in STEP 7 The procedure depends on the version of STEP 7: Up to STEP 7 V5.4 SP1 If the WinCC flexible project integrated in STEP 7 is to be archived without information for the delta compile, you can delete the following files. All files with the name "Project_n_{{..............................}}.data" e.g. -> PROJECT_1_{{9f58e235-cb6e-40eb-829f-e23350eedaca}}.data Project_n.Device_1.fwx e.g. -> PROJECT_1.SIMATIC HMI Station(1).fwx The files are located in your STEP 7 project directory under "HmiES  > Devicename_n >" e.g. "HmiES  > PROJECT_1 >"  ( 41 KB ) Fig. 02 Then archive your STEP 7 project as usual. The next time you open the project, the files deleted previously are automatically regenerated. From STEP 7 V5.4 SP2 onwards From STEP 7 version V5.4 SP2 onwards, you can use the archiving method of the SIMATIC Manager (File > Archive...). The WinCC flexible files are automatically reduced to files required for restoring your project. The next time you dearchive and open the project, the files deleted previously are automatically regenerated.

 

No.	Project archiving in WinCC flexible 2004 / 2005
1	Standalone project (a WinCC flexible project not integrated in STEP 7) If just the WinCC flexible project is to be archived without information for the delta compile, then only the following files are required. ProjectName.hmi ProjectName_log.ldf The files are located in the relevant project directory. The next time you open the project, the files deleted previously are automatically regenerated. "Attachment 2" contains a breakdown of WinCC flexible files based on a sample configuration. Attachment 2: Project_Data_2004.zip ( 11 KB )
2	WinCC flexible integrated in STEP 7 If the WinCC flexible project integrated in STEP 7 is to be archived without information for the delta compile, then only the following files of WinCC flexible are required. GuidId.bin GuidTp.bin IdGuid.bin ProjectName.devices ProjectName.hmi ProjectName_log.ldf The files are located in your STEP 7 project directory under "HmiES  > Devicename_n >" e.g. "HmiES  > PROJECT_1 >"  ( 31 KB ) Fig. 03 The next time you open the project, the files deleted previously are automatically regenerated.

Notes on migration
Opening a WinCC flexible project that is based on a previous version.
When you open a WinCC flexible ES project with more recent version of WinCC flexible ES, a message is displayed during the opening procedure indicating that the project to be opened has been created with a previous version of WinCC flexible.

( 25 KB )
Fig. 04

Acknowledge the message with the "OK" button and WinCC flexible automatically creates a backup file. The file is located in the same project directory as the remaining configuration.
You recognize the backup file generated by the names "Project_name.backup.hmi" and "Project_name.backup_log.LDF".

Example
MP370_Touch.backup.hmi, MP370_Touch.backup_log.LDF
You can archive these files elsewhere. They are not necessary for the WinCC flexible configuration.

Keywords:
Project archiving, Project file 

Sumber: http://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&lang=en&objid=21896449&caller=view

Salah satu tahapan terpenting sebelum melakukan comissioining mesin yaitu continuity test. Lebih lengkap silahkan baca artikel ini.

What is continuity?

Mengapa mengukur Arus Listrik Menggunkan Tang Ampere?

Salah satu alat yang diperlukan pada saat kita melakukan commissioning dan pengujian arus listrik "test and run" mesin atau alat-alat yang menggunakan listrik lainnya dilapangan.

Clamp meters allow for measurement of current, without needing to disconnect the wires where the measurement occurs. By simply clamping the wire, you can get the measurement, and not cut the circuit. When using a multitester or a digital multimeter, the circuit has to be cut. In contrast, using a clamp meter, current can be measured by clamping a live wire over its sheath. In addition to its simple operation, it allows safe measurement of a higher current.

Clamp meters feature low internal resistance and have both a positive and negative lead. High current flow can indicate a short circuit, a defective component, or an unintentional ground. Low current flow can indicate high resistance, or poor current flow within the circuit. Both types of clamp meters (digital and analog) are designed to measure levels of direct current (DC) and alternating current (AC). Most products have built in sensors. Some clamp meters can test diodes or transistors while others can monitor thermocouples or resistance temperature detector (RTD) values. Some may adjust sampling rates automatically, display status information as a bar graph, and measure decibel (dB) readings. Our specialty clamp meters provide special measurement types and optional features. Some can test diodes or transistors. Others can monitor thermocouples or resistance temperature detector (RTD) values. Programmable clamp meters provide internal data storage and will allow you to establish activation triggers. Clamp meters are extremely useful and allow for many types of safe electrical testing.

Please visit Fluke Website for your information.

Using a Multimeter

A multimeter is used to make various electrical measurements, such as AC and DC voltage, AC and DC current, and resistance. It is called a multimeter because it combines the functions of a voltmeter, ammeter, and ohmmeter. Multimeters may also have other functions, such as diode and continuity tests. The descriptions and pictures that follow are specific to the Fluke 73 Series III Multimeter, but other multimeters are similar.

Important note: The most common mistake when using a multimeter is not switching the test leads when switching between current sensing and any other type of sensing (voltage, resistance). It is critical that the test leads be in the proper jacks for the measurement you are making.

Safety Information

• Be sure the test leads and rotary switch are in the correct position for the desired measurement.
• Never use the meter if the meter or the test leads look damaged.
• Never measure resistance in a circuit when power is applied.
• Never touch the probes to a voltage source when a test lead is plugged into the 10 A or 300 mA input jack.
• To avoid damage or injury, never use the meter on circuits that exceed 4800 watts.
• Never apply more than the rated voltage between any input jack and earth ground (600 V for the Fluke 73).
• Be careful when working with voltages above 60 V DC or 30 V AC rms. Such voltages pose a shock hazard.
• Keep your fingers behind the finger guards on the test probes when making measurements.
• To avoid false readings, which could lead to possible electric shock or personal injury, replace the battery as soon as the battery indicator appears.

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Input Jacks

The black lead is always plugged into the common terminal. The red lead is plugged into the 10 A jack when measuring currents greater than 300 mA, the 300 mA jack when measuring currents less than 300 mA, and the remaining jack (V-ohms-diode) for all other measurements.

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Range

The meter defaults to autorange when first turned on. You can choose a manual range in V AC, V DC, A AC, and A DC by pressing the button in the middle of the rotary dial. To return to autorange, press the button for one second.

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Automatic Touch Hold Mode

The Touch Hold mode automatically captures and displays stable readings. Press the button in the center of the dial for 2 seconds while turning the meter on. When the meter captures a new input, it beeps and a new reading is displayed. To manually force a new measurement to be held, press the center button. To exit the Touch Hold mode, turn the meter off.

Note: stray voltages can produce a new reading.

Warning: To avoid electric shock, do not use the Touch Hold to determine if a circuit with high voltage is dead. The Touch Hold mode will not capture unstable or noisy readings.

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AC and DC Voltage

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Resistance

Turn off the power and discharge all capacitors. An external voltage across a component will give invalid resistance readings.

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Diode Test

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Continuity Test

This mode is used to check if two points are electrically connected. It is often used to verify connectors. If continuity exists (resistance less than 210 ohms), the beeper sounds continuously. The meter beeps twice if it is in the Touch Hold mode.

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Current

Warning: To avoid injury, do not attempt a current measurement if the open circuit voltage is above the rated voltage of the meter.

To avoid blowing an input fuse, use the 10 A jack until you are sure that the current is less than 300 mA.

Turn off power to the circuit. Break the circuit. (For circuits of more than 10 amps, use a current clamp.) Put the meter in series with the circuit as shown and turn power on.