Phenix Technologies MRM-100 User manual

Users Manual
Phenix Technologies Inc.
MICRO-OHMMETER
MODEL NUMBER MRM-100
Version 1.1
DK/ELL/LEO/slu
May, 2004

TABLE OF CONTENTS
Section Number
GENERAL SAFETY PRECAUTIONS
PRODUCT INFORMATION 1
-SAFETY AND CAUTION NOTES
-SPECIFICATIONS
-INTRODUCTION / THEORY OF OPERATION
CONTROLS AND INDICATORS 2
ELECTRICAL SET-UP 3
MRM MENU TREE 4
STARTING SCREENS 4-1
PERFORMING TESTS 4-2
SAVED RESULTS 4-6
SYSTEM SETUP 4-8
OPERATING INSTRUCTIONS 5
UNIT UNDER TEST 5-1
METER CHECK 5-2
TROUBLESHOOTING OPERATIONAL PROBLEMS 6
STORAGE OF EQUIPMENT 7
MAINTENANCE 8
RECOMMENDED SPARE PARTS 9
MRM-100 PARTS LIST 10
PARTS ORDERING INFORMATION 11
RETURNED MATERIAL 12
ELECTRICAL DIAGRAMS 13

1-1
PRODUCT INFORMATION
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
CAUTION: Contact with the test leads on this equipment can cause
harmful electrical shock. Do not touch test leads while a test is in process.
SAFETY AND CAUTION NOTES
1. Contact with the test leads on this equipment can cause harmful electrical shock. Do not
touch test leads or test object while a test is in process.
2. Insure the micro-ohmmeter is properly grounded through the power cord before proceeding
with a test.
3. Turn the micro-ohmmeter off and unplug power cord before reaching inside. Damage to the
tester and hazardous shock to personnel will result if this procedure is not followed.
4. Insure that the equipment to be tested is de-energized and properly isolated.
5. Use care to avoid damaging the micro-ohmmeter during disassembly and re-assembly
procedures.
6. This unit should only be operated by someone familiar with high current testing and safety
procedures.
Phenix Technologies, Inc. assumes no liability for unsafe or improper use of test equipment.

1-2
PRODUCT SPECIFICATIONS
Input:
100 to 240 VAC, 50/60 Hz, single phase, 5 Amps.
Resistance Measurement Range:
1µΩ to 240mΩ, non-inductive.
Test Current:
10 to 105 Amps, selectable in 1 Amp steps.
Uncertainty:
+/- 1% of reading, +/- 0.4µΩ at 100 Amps or +/-4µΩ at 10 Amps.
Resolution:
1µΩ to 199µΩ: 0.1µΩ
200µΩ to 1999µΩ: 1µΩ
2.00mΩto 19.99mΩ: .01mΩ
20.0mΩto 240.0mΩ: 0.1mΩ
Termination:
30 foot cables with alligator clamps. C clamps are also available
Keyboard:
10 number keys, 26 letter keys, and 14 function keys.
Control:
Embedded microprocessor
Display:
4 X 20 LCD screen
Computer Port:
RS-232 ASCII Commands
Memory:
The MRM-100 can store up to 300 measurements in memory.
Type of Cooling:
Two cooling fans
Uncertainty Temperature Range:
18°C to 27°C (64°F to 81°F)
Operating Ambient Temperature:
-7°C to 45°C (19°F to 113°F)
Storage Temperature:
-20°C to 57°C (-4°F to 135°F)
Dimensions:
16.5” W x 15.25” D x 11.25” H (419 mm W x 388 mm D x 286 mm H)
Weight:
Unit: 28.5 lbs. (13 kg)
Cables/ Bag/Accessories: 19.5 lbs. (8.8 kg)

1-3
INTRODUCTION
The MRM-100 is a portable micro-Ohmmeter used to test circuit breaker
contact resistance, or anywhere low resistance measurements at currents up to
just over 100 Amps are required. The MRM-100 uses a low voltage, high current
power supply to run a user-defined test current of between 10 Amps to 105
Amps to any resistive load that requires no more than 2.5 Volts across it to test.
The MRM-100 does detect if the test is able to reach desired current, and allows
for immediately stopping the test.
THEORY OF OPERATION
The MRM-100 uses a two-voltmeter method where each voltage reading
implements a four-wire Kelvin connection. One voltmeter monitors the voltage
across a known, highly stable shunt that passes the test current through it, while
the other voltmeter monitors the voltage across the unit under test. A test
current is then applied (see ANSI C37.09 and IEC 62771-100 for test current
requirements). This current is ramped up, held for a period of time and then
ramped down. While the current is relatively constant, the voltages across the
known resistance and unit under test are amplified and filtered. Then they are
sampled several times by analog to digital converters to reduce any noise, and
processed by a microcontroller. The microcontroller calculates the ratio between
the test current and sensed voltage to determine the resistance. The micro-
Ohmmeter is designed to test resistances of 1 micro-Ohm to 240 milliohms.

2-1
CONTROLS AND INDICATORS
1. AC Line Cord Input Connector:
Plug into a suitable grounded receptacle. See specifications for voltage and current
requirements.
2. Main Power Switch:
Turning the switch On / Off energizes or de-energizes the MRM.
3. RS-232 Port:
This port allows communication with a Personal Computer for data acquisition and remote
control, when supported by appropriate optional software.
4. LCD Display:
This 4x20 Character display, shows all relevant information during testing and setup.
5. Keypad:
This keypad is used to enter test parameters.
6. Built In Printer:
The built in dot matrix printer is designed to print test results immediately or to provide a
printout of saved tests.
I
SERIAL I/O
0
AC INPUT
MODEL MRM-100
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H
Y
N
Space
6
F
DG
A S
Esc
Z,
-/
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V
C
XB
Q
1
R
ET
W
235
4
Enter
KL
J
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Start Stop
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SENSE
OFF ON
CURRENT
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MRM-100
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PHENIX
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TECHNOLOGIES
R
RS-232
OUTPUTS
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2-2
CONTROLS AND INDICATORS (Continued)
7. High Current Output Connection
This receptacle is for connection of the high current output leads.
8. Output Energized Indicator:
This indicator illuminates under any of the following conditions:
a. A test is in progress.
No test cables should be connected, disconnected or handled while this light is on.
9. Output Sense Lead Connection:
This receptacle is for connection of the sense leads required for the four wire measurement.

3-1
ELECTRICAL SET-UP
Line / Generator Powered Operation
Locate the desired location for the test set. Prepare the main power input cable for plugging into
the proper facility or generator power. Leave plug unconnected at this time. Ensure that generator
is properly grounded with facility ground or ground (earthing) rod.
Measurement Lead Connection
WARNING: Main power switch on front panel must be in the OFF position before
proceeding. Insure test specimen is de-energized, discharged, and properly isolated!
1. Connect the measurement cables with red leads to the positive terminal (if applicable) of the
unit under test.
2. Connect the measurement cables with black leads to the negative terminal (if applicable) of
the unit under test.
3. Connect the input main power cable to appropriate power source if powering with line power.
Note: Specimen connection points for test cables must be clean and corrosion free. Any
contamination at connection points may result in errant readings.

4-1
MRM MENU TREE
STARTING SCREENS
MRM START UP SCREEN
Press any key (except “Esc”) to proceed.
TEST OPERATOR ID SCREEN
Operator identification may be entered here and is shown on printouts as
well as saved tests. Leave blank if not wanted for test. To delete the
existing entry, move cursor to the left with left arrow and use delete key.
MRM MAIN MENU
The following numbers are keyed to the screen shot above.
1) If “1” is pressed, a test setup is begun.
2) If “2” is pressed, the operator identification can be altered.
3) If “3” is pressed, saved results can be recalled.
4) If “4” is pressed, the meter itself can be set up.
5) If “1” is pressed, the following screen is displayed.

4-2
PERFORMING TESTS
TEST DESCRIPTION SCREEN
Any information about the next test can be given here (up to 20
characters).
TEST CURRENT SET-UP
Any current from 10Amps to 105Amps (in one amp steps) can be entered
here. The actual test current will vary somewhat from the entered current
but will be close. If current as entered results in a level slightly below the
minimum or slightly above the maximum allowed for test, entry can be
changed by one amp steps to bring current level within specification.

4-3
READY FOR TEST SCREEN
When “Enter” is pressed, the meter shows the following screen:
This screen shows information about the test and how to begin.
1) This shows at what current the test will be at.
2) This displays the test ID information entered.
3) The green “Start” button on the keypad begins the test.
TEST IN PROGRESS SCREEN
This screen is what is shown while the test is running.
1) This is the approximate current the test is run at.
2) This is the current being measured. This should ramp
up to about the current shown on the first line.
3) If the test current is to be cut off, press the red “Stop”
button on the keypad.
4) This warns the user (along with the beeper and the red warning
light) there may be a high current going through the test cables.
When the test is completed, the following screen will appear.

4-4
RESULT SCREEN
This shows the measured resistance as well as the actual test current.
The top line is shown only until “S” is pressed. The last line gives options
as well as affirms these are the results. To return to the Main Menu from
this screen, press “ENTER” and “Esc”
If “Enter” is pressed, the following screen appears.
CONTINUE SCREEN
1) The first line will appear if the test has not yet been saved to memory.
2) This reminds the user how the test can be saved.
3) To repeat the test at the same current and test ID, press “R”.
4) To run a different test press “Enter”.
If for some reason the operator presses the “Stop” key while a test is in
progress, the following screen appears:

4-5
TEST ABORTED SCREEN
From here, pressing any key gives the following screen:
ABORTED CONTINUANCE SCREEN
This gives the user the option to retest the unit at the same current and
test ID, or start a new test.
Pressing “Esc” will return user to the main menu.

4-6
SAVED RESULTS
Pressing “3” at the MRM Main Menu screen for “Saved Results’ produces
the following screen.
SAVED RESULTS SCREEN
Information provided by this screen is:
1) Saved test number, and
2) The day and time the test was performed.
A test identifier typed in by the operator is also given.
The screen can scroll between the different saved tests as well as
give options to see or print the data. If “P” is pushed, complete
information for the selected saved test is printed.
If “D” is pressed to see the data one gets the following screen:

4-7
SAVED DATA SCREEN
This gives the results of the saved test.
To return to the main menu, press “Esc” as appropriate. At some
instances, “Enter” must be pressed before “Esc” is allowed.

4-8
SYSTEM SETUP
If “4” is pressed, one gets to the two screens (which can be toggled by the
up/down arrows).
SYSTEM SETUP SCREENS
The six setup options are:
1) A. Viewing and setting the time for the meter
2) B. Viewing and setting the date for the meter
3) C. Viewing the unit counter (which tells how many tests have been
run).
4) D. Viewing and setting the meter’s calibration values (generally only for
factory use).
5) E. Viewing and setting the current ramp rate. The ramp up/down
speeds are approximately:
-1- 10 Amp/sec
-2- 15 Amp/sec
-3- 25 Amp/sec
-4- 35 Amp/sec
-5- 55 Amp/sec
6) F. Company name or other desired information can be entered for
display on printouts.
If option “A” is pressed, the following screen appears:

4-9
SET TIME SCREEN
The “1” arrow shows the hours and minutes which can be changed. The
meter can also give the time in AM/PM or 24 hour time.
If option “B” is pressed the date screen appears.
SET DATE SCREEN
Here the date can be modified per the instructions on the last line. To
move around on the screen use the blue arrow keys on the keypad.
If option “C” is pressed, the counter screen appears.
UNIT COUNTER SCREEN
This number will increment for every test performed, whether it is saved or not.

5-1
OPERATING INSTRUCTIONS
UNIT UNDER TEST
1) Follow the Setup Instruction described in the “ELECTRICAL SETUP SECTION”
TYPICAL UNIT UNDER TEST HOOK UP.
2) Turn On Power.
3) Wait for the system to boot and press any key to continue.
4) Enter the operator ID if desired. Press “Enter” twice.
5) Press “1” in the Main Menu.
6) Enter the test ID information if desired. Press “Enter” twice.
7) Enter the test current desired. Press “Enter” twice.
8) Press the green “START” button.
9) The instrument will make a beeping sound and the “Warning: Test in Progress” light will come
on.
10) Upon completing the test, the results will be displayed unless there is an error. Press “P” to
print, “Enter” to continue, or “S” to save.
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Space
6
F
DG A S
Esc
Z,
-/
.
V
C
XB
Q
1
R
ET
W
2354
Enter
K L
J


Start Stop

M
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IP
O
U
8
7 0
9
MRM-100
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PHENIX
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TECHNOLOGIES
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5-2
OPERATING INSTRUCTIONS
METER CHECK
METER VERIFICATION HOOK UP
1) Follow the Setup Instruction described in the “ELECTRICAL SETUP SECTION”, using the
supplied 100 Amp, 100 milliVolt current shunt.
2) Turn On Power.
3) Wait for the system to boot and press any key to continue.
4) Enter the operator ID information. Press “Enter” twice.
5) Press “1” in the Main Menu.
6) Enter the test ID information, if available. Press “Enter” twice.
7) Enter the test current desired. Press “Enter” twice.
8) Press the green “START” button.
9) The instrument will make a beeping sound and the “Warning: Test in Progress” light will come
on.
10) Upon completing the test, the MRM-100 should give a result between 987 and 1013 micro-
Ohms at 100 Amps or between 983 and 1017 micro-Ohms at 10 Amps.
 
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TECHNOLOGIES
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H
Y
N
Space
6
F
DG A S
Esc
Z,
-/
.
V
C
XB
Q
1
R
ET
W
2354
Enter
K L
J


Start Stop

M

IP
O
U
8
70
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MRM-100