3M Electronic Marking System EMS Marker Locator with iD ReadWrite 7420 User Manual

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7. Reading 3M™ iD Markers
The operator can retrieve the data from the 3M™ iD Marker by pressing Read [SK] on 
the Marker Locate screen.
The locator tip should be lowered to the ground to reach maximum read depth.
If more than one iD marker of the same utility is detected, the locator will read the first 
marker and display the data from the marker.
The fourth yellow command key will be labeled 
“Read Next”. Press this key to extract the data from 
the other marker.
All the information retrieved from the marker, including the date and time read, is 
saved into the ‘Read History’ file of the locator. If a hand-held GPS device is used in 
conjunction with the locator, coordinates can be saved into the Read History.  
(See  8. Reviewing Marker Read/Write History)
8. Reviewing Marker Read/Write History
A.  Read History
The Read History mode is a historical file of all information that has been read from 
targeted markers (100 memory locations).
Menu [6] + Data/Templat [SK:2] + Read History [SK:2a]
The Read History screen displays the date and 
time that each marker was read, and its unique 
identification number.
• Select the marker data to be viewed by pressing 
the up/down arrows [SK]
•  Press  Marker Details [SK] to view all data that 
was retrieved from the marker.
•  Press  Read History [SK] to return to the list or 
press  Exit [SK] to return to Data/Template review 
display. 
						

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B. Write History
Menu [6] + Data Templat [SK:2] + Write History [SK:2b]
• Select the marker data to be viewed by pressing 
the up/down arrows [SK].
•  Press  Write Details [SK] to view all data that was 
sent to the marker.
•  Press  Write History [SK] to return to the list of 
written data.
•  Press  Exit [SK] to return to Data/Template review 
display.
For additional information concerning writing to 3M™ iD Markers, refer to 
www.3M.com/dynatel  - Instruction Manual M-Series Locator PC Tools.
9. GPS Compatibility Operation
A.  Activation Key
To activate the GPS compatibility in the locator, an activation key must be entered into 
the locator. The software version of the locator must be at least version 14 (See 9.B. 
Serial Number and Software Version to verify the locator software version). For the 
locator to transmit information to the GPS for use in GIS mapping applications (see 
9.F. Sending iD Marker Data to GPS (Capture-Transmit Mode / Mode 2) section ), the 
hardware version must be 5.0 or higher. (See 9.B. Serial Number & Software Version 
Section .)
The 3M
™ Dynatel™ PC Tool Kit software is available free of charge at www.3M.com/
dynatel under the Software section; 2550/2573/2250M/2273M/7420 Locator PC Tools 
xx.x.x (EXE xx.xMB). The GPS activation key can also be obtained from this website 
free of charge. You will be asked to enter the serial number of the locator and a few 
other information items in order to receive the GPS activation key.
Upgrade the software of the locator using the desktop software, if necessary, using  
3M
™ Dynatel™PC Tool Kit. Enter the GPS activation key on the locator.
B.  Serial Number and Software Version
Menu [6] + >>More [SK:4] + Self Test [SK:7]
The model number, serial number, software version, and hardware version of the 
locator are displayed. The Self Test Mode can also be run from this screen by pressing 
Run [SK]. 
						

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C. Inputting the GPS Activation Key
Menu [6] + COM Setup [SK:3]
Initially, when the COM  [SK:3] key is pressed, and an attempt is made to enable any 
selection other than PC, the screen below will appear and you will be prompted to 
input the activation key that you have obtained from the website. This will have to be 
performed only one time to enable the GPS interface.
•  Move the selector box left or right by pressing the 
arrow keys [SK].
•  Press  Select  [SK] to enter each number.
•  Press  OK [5] to activate.
D. Communicating with the GPS Device
Menu [6] + COM Setup [SK:3]
After the GPS interface has been activated, the COM Setup [SK:3] key will toggle 
through several options to configure the Serial Port [14] of the locator (depending on the 
application, or capabilities of the GPS device). Select from the following options.
NMEA  – The Serial Port is configured to receive NMEA signals from a GPS device 
(4800 Baud Rate). (Capture Mode/Mode 1)
GIS  – The Serial Port is configured to send and receive data to a GPS device that has 
GIS mapping capabilities. (Capture/Transmit Mode/ Mode2)
PC  – The Serial Port is configured to communicate with a computer for the Dynatel PC 
Tool Kit application
PDA  - The Serial Port is configured to only send information if the GPS device only has 
the ability to receive information.
E.  Capturing GPS Coordinates (Capture Mode / Mode 1)
Menu [6] + COM Setup [SK:3] + NMEA
If the GPS device is not configured properly, there is an error communicating with the 
locator, or the GPS has not acquired enough satellites to pinpoint the location, the locator 
will display the message “Insert External Device”.
When the locator is communicating with a GPS 
device, the LAT and LONG coordinates received from 
the device will appear on the marker locate display.
Step 1.  Locate a marker (See 4. D. Single Marker Locate.)
Step 2.  Press Read [SK] 
						

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The information from the iD marker, as well as the GPS coordinates, will display on the 
locator display. This information is saved automatically in the Read Marker History. (See 
8.A. Reviewing Marker Read/Write History.)
If the marker is a passive marker (rather than iD) the locator will display “No iD Marker 
Found”. The GPS coordinates of the attempt to read the non-iD marker are stored in 
the Read Marker History as serial number # 0000-0000-0000. The marker details will 
indicate “not an iD marker”, but will display the GPS coordinates.
F.  Sending 3M™ iD Marker Data to GPS (Capture-Transmit Mode / 
Mode 2)
Menu [6] + COM Setup [SK:3] + GIS
Locators that have marker locating capability (indicated by ‘iD’ in the model number 
or description) can be configured to send 3M
™ iD Marker data directly to some GPS 
devices. When an iD marker is located and read, the information read from the iD 
marker, with feature and attribute data, is sent to the GPS device and is stamped with 
latitude, longitude and date/time data. The data acquired during this logging process can 
be uploaded to GIS mapping software. For more information and detailed instructions 
pertaining to specific GPS devices, refer to www.3M.com/dynatel for GPS instruction 
sheet.
10.  Help Mode
Menu[6] + >>More [SK:4] + Help [SK:8]
The help screen contains basic information about the locator and its operation. It is 
designed to be a quick reference guide.
• Press the double up/down arrows [SK] to navigate between sections.
 
− The single up/down arrows [SK] will scroll the display line by line. 
						

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11. 3M™ Dynatel™ PC Tool Kit and 
Locator Software Upgrades
Locator software upgrades are periodically released and can be downloaded, free of 
charge, at www.3M.com/dynatel . Located under the Software section, the software is 
titled  2550/2573/2250M/2273M/7420 Locator PC Tools xx.x.x (EXE xx.xMB). Once 
downloaded to your PC, double click the file and an auto-installer will install the 
PC  Tool desktop software. Double click the Dynatel PC Tool Kit icon on the desktop. 
Using the provided RS232 cable, or RS232-to-USB adapter cable, connect the Serial 
Port [14] on the locator to the PC and power the locator on. Click the Upgrade Software 
button in PC Tools to begin upgrade. Do not disconnect or power off the locator while 
the upgrade is in progress. Wait until the software indicates that the installation was 
successful. This will take approximately seven minutes to complete. 
The  Dynatel PC Tool Kit provides the user an excellent interface between the locator and 
a PC. This software utility provides the tools for:
•  Upgrading the locator to the latest software revision
•  Programming one or multiple locators to best suit specific user configurations
•  Loading an alternate language into the locator
•  Using the 3M
™ iD Marker utility to:
 
− Create templates for writing data to iD markers, or create Trace Templates for 
GPS path tracing when connected to a GPS device.
 
− Download iD marker data that has been written or read by the locator for 
documentation databases.
Embedded in the desktop software is the most current software for the locator, which 
affords the user the option of upgrading the unit without returning the unit to the 
3M Service and Repair Center.
Please refer to the operating instructions included with the software.
12.  Memory Self Test
Menu [6] + >>More [SK:4] + Self Test [SK:7]
This operation performs a self-test on the locator.
The locator will display current information about the unit (model number, serial 
number, software revision, and hardware revision).
1.  Press  Run [SK] to start the self test.
 
− A status bar will appear while the self test is running.
 
− Results will appear on the display when the test is complete.
 
− Press Exit [SK] to return to the Menu. 
						

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13. Replacement Accessories
Item Part Number
AC Charger for 7000RB  Rechargeable   
Battery Pack 7000CH
Rechargeable Battery Pack for   
7000 Series Rcvr  7000RB
14. 
3M™ Dynatel™ EMS Marker/Tape Locator 
7420/7420E Product Specifications
Physical Specifications:
Locator
Shipping Box Size (H x W x D) IN (CM) 
30" x 6.5" x 10.5" (76 x 17 x 27)
Size (L x W x H) IN (CM)
33" x 17" x 12.5" (84 x 43 x 32) Weight (including 
batteries)
5 lb. (2.25 kg)
7 lb. (3.2 kg)
Environmental Specifications:
Operating temperature 
Storage temperature 
Regulatory 
Environmental Standard  -4° F to 122° F (-20° C to 50° C)
-4° F to 158° F (-20° C to 70° C)
7420 (FCC Part 15), 7420E (CE)
IP54
Compatibility:
3M
™ EMS/iD Markers 
3M
™ EMS 7600 Series Caution 
Ta p e All 3M markers (telephone, gas, 
communication, power, water, 
wastewater and general purpose)
All 3M path marking caution tape 
(telephone, gas, water)
Range/Depth: 
Maximum Write Range
3M
™ iD Markers: (Telephone,Gas, Water, Wastewater 
Communications (CATV), General 
Purpose)
Near-Surface
Ball Marker
Full-Range 6 in (15 cm)
12 in (30 cm)
24 in (61 cm)
7420 Maximum Read Range   
3M
™ iD Markers (with ID): (Telephone, Power, Gas, Water, 
Wastewater, Communications 
(CATV), General Purpose)*
Near-Surface
Ball Marker
Full-Range 3 ft (0.9 m)
5 ft (1.5 m)
8 ft (2.4 m) 
						

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7420E Maximum Read Range 
3M™ iD Markers (with ID):(Telephone, Power, Gas, Waste-
water, Communications (CATV), 
General Purpose) Water*
Near-Surface
Ball Marker
Full-Range 90 cm (36 in)
1.5 m (60 in)
2.4 m ( 96 in) 60 cm (24 in)
1.0 m (40 in)
2.0 m (78 in)
* Some countries do not allow all marker operating frequencies. Refer to Configuration Section 
for 7420E (Section 4A).
Maximum Detection Depth
Passive Markers (no ID):
Near-Surface
Ball Marker
Mid-Range
Full-Range 3 ft (0.9 m)
6 ft. (1.8 m)
7 ft. (2.1 m)
9 ft. (2.75 m)
Maximum Detection Depth
7600 Series CT-3 Tape
Depth measurement accuracy 2 ft (0.6 m)
+/- (10% + 5 cm) or +/- (10% + 2 in) up to specified 
depth of marker or caution tape (Depth accuracy 
susceptible to high ambient noise conditions)
iD Marker Memory Storage:
Memory storage with date/time 
stamp
Written marker records       
User defined iD templates   
Marker depth memory storage  Read marker records 100
 
100
32
Five with date/time stamp
Electrical Specifications:
Power 
Battery life: 
Charging time
Display 
Speaker 
Headphone jack 
Serial port  Rechargeable Li Ion battery pack (12V2R4A)
1 
8 hours typical2
2.5 hours typical, with 90~240V AC adapter
Large graphic high-contrast LCD with backlight
0.25W
Standard mini phone jack
Standard RS232 serial with DB9 connector  
(RS232 to USB adapter cable included)
Notes:
1.   It's recommended to use the rechargeable battery pack. However, a battery holder is provided for using 
8-AA size Alkaline batteries for backup, which would have reduced battery life. 
2.    The battery life is specified for the 12V2R4 rechargeable battery pack at 73°F / 23°C, with 10% usage of the 
backlight and audio volume at medium level.  
						

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Important Notice
All statements, technical information and recommendations related to 3M Products are based on information 
believed to be reliable, but the accuracy or completeness is not guaranteed. Before using the 3M Product, 
you must evaluate it and determine if it is suitable for your intended application. Because conditions 
of Product use are outside of our control and vary widely you assume all risks and liability associated 
with such use. Any Product-related statements not contained in current 3M publications, or any contrary 
statements contained in your purchase order, shall have no force or effect unless expressly agreed to in 
writing by an authorized officer of 3M.
Limited Product Warranty
3M Locators (except accessories), will conform to 3M’s published specifications and will be free from 
defects in material and manufacture for a period of twelve (12) months from the date of purchase. Dry 
cell batteries included in any of 3M’s products are warranted only to the extent the battery manufacturer 
determines such batteries are covered by its warranty. Locating accessories are warranted for ninety (90) 
days after purchase. 3M’s obligations and liability under this warranty are limited to repairing, replacing or 
refund of the purchase price, at 3M’s option, any of 3M’s products which, after normal and proper usage, are 
determined by 3M to be defective. This warranty does not extend to any of 3M’s products which have been 
subjected to misuse, neglect, accident or improper applications, nor shall it extend to products which have 
been repaired or substantially altered outside 3M’s manufacturing or repair facility, nor to any associated 
instruments, equipment or apparatus. Before utilizing any of 3M’s products, BUYER should determine the 
suitability of the product for BUYER'S intended use. 3M MAKES NO OTHER WARRANTIES, EXPRESSED 
OR IMPLIED, INCLUDING ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A 
PARTICULAR PURPOSE. In no case shall 3M be liable for any special, incidental, or consequential damages 
based upon breach of warranty, breach of contract, negligence, strict liability or any other legal theory. This 
limitation does not apply to claims for personal injury. 
Special Condition: Shipments into authorized distributor/supplier locations will have an additional ninety 
(90) day warranty period. 
3
Infrastructure Protection Division6801 River Place Blvd.
Austin, TX 78726-9000
1-800-200-0265
FAX: 1-877-601-1305
www.3M.com/dynatel Please Recycle. Printed in USA.
© 3M 2012. All Rights Reserved.
78-9000-0431-4-C
This product is in accordance with the requirements of the 
European directive 99/5/EC.
This is the EU symbol f
or equipment that is covered 
under the W aste from Electr ical and Electronic 
Equipment (WEEE) directiv e per CENELEC 
Specification 5041.  It indicates that cert ain products 
should not be discarded in the trash,  but rather 
should be recycled.   This applies to all electronic 
pluggab le and batter y powered product s.This is the EU symbol for equipment that is covered under the Waste 
from Electrical and Electronic Equipment (WEEE) directive per CENELEC \
Specification 5041. It indicates that certain products should not be 
discarded in the trash, but rather should be recycled. This applies to all 
electronic pluggable and battery powered products.