MG MDP-LC User manual

EM-8128 Rev.10 P. 1 / 3
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
INSTRUCTION MANUAL
LIGHTNING SURGE PROTECTOR FOR
STRAIN GAUGE USE MODEL MDP-LC
BEFORE USE ....
Thank you for choosing us. Before use, please check con-
tents of the package you received as outlined below.
If you have any problems or questions with the product,
please contact our sales office or representatives.
■PACKAGE INCLUDES:
Surge protector....................................................................(1)
DIN rail mounting adaptor*...............................................(1)
Screws for DIN rail mounting (M4 × 8)* ...........................(2)
*Included with option code /A33
■MODEL NO.
Confirm Model No. marking on the product to be exactly
what you ordered.
■INSTRUCTION MANUAL
This manual describes necessary points of caution when
you use this product, including installation, connection and
basic maintenance procedures.
LIMITATION APPLICABLE TO M-RESTER
The M-RESTER will protect electronics equipment from
damage caused by lightning by absorbing most of the
surge voltages.
However, M-RESTER may not be effective against cer-
tain extremely high voltages caused by a direct or almost
direct hit by lightning.
M-RESTER must be installed according to this installa-
tion / instruction manual.
GENERAL
■FUNCTION & FEATURES
• Designed to protect strain gauge transmitters from light-
ning surge damage that enters on the wiring between the
strain gauge and the transmitter
• Absorbs surges only without affecting instrumentation
signal
• No interruption of signal by unplugging the protector el-
ement
■SPECIFICATIONS
OUTPUT
SIDE
EXCITATION
SIDE
LINE TO
EARTH
Max. continuous
operating voltage (Uc)
±0.3V. 15V ±15V
Voltage protection level
(Up) @Imax
±15V 30V ±30V
Max. discharge current
(Imax) (8 / 20 µs)
100A 50A 50A
Max. discharge current
(Imax) (10 / 1000 µs)
25A 25A 25A
Leakage current ≤ 0.2µA
@±0.3V DC
≤ 2µA
@15V DC
≤ 2µA
@±15V DC
Capacitance @1 MHz ≤ 100 pF ≤ 4 nF ≤ 2 nF
Response time ≤ 5 nanoseconds
POINTS OF CAUTION
■ENVIRONMENT
• When heavy dust or metal particles are present in the
air, install the surge protector inside proper housing with
sufficient ventilation.
• Do not install the surge protector where it is subjected to
continuous vibration. Do not subject the unit to physical
impact.
• Environmental temperature must be within -5 to +55°C
(23 to 131°F) with relative humidity within 30 to 90% RH
in order to ensure adequate life span and operation.
■DIELECTRIC STRENGTH TEST
• Loosen the screw located at the left-center of the element
and remove the element module from the base before
conducting a dielectric strength testing. Otherwise the
element will start discharging at a voltage exceeding the
max. continuous operating voltage (Uc), which can cause
insulation failure of the module.
Be sure to return the element and fasten securely after
the test.
■AND ....
• We recommend that you keep spare surge protectors so
that you can replace them when necessary.
• Lightning surge can enter not only through signal lines
but also through power supply lines. We recommend that
you also use the surge protectors for power line for suffi-
cient protection.
COMPONENT IDENTIFICATION
M•RESTER
Ground Terminal (G)
(used as mounting bracket)
Head Element Base
Specifications
Head Element is secured to Base
with screw when the surge protector
is shipped from Factory.

MDP-LC
EM-8128 Rev.10 P. 2 / 3
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
INSTALLATION
In order to separate the head element from the base, loosen the screw located at the left-center of the element.
■WALL MOUNTING
Refer to the drawings below.
• EXTERNAL DIMENSIONS unit: mm (inch)
25 (.97) min. 2–M4 SCREW
90 (3.54)
• MOUNTING REQUIREMENTS
unit: mm (inch)
–
+
L2L1
23.5 (.93)
80 (3.15)
2–5 (.20) dia.
MTG HOLE
90 (3.54)
100 (3.94)
4–M4 TERMINAL SCREW
GROUND TERMINAL (G)
(used as mounting bracket)
27 (1.06)53 (2.09)
80 (3.15)
45 (1.77)
HEAD ELEMENT
BASE
■DIN RAIL MOUNTING (Only for /A33)
1. MOUNTING ONTO THE ADAPTOR
Before DIN rail mounting, secure the mounting bracket of
MDP to the mounting adaptor with a screw provided with
this product. In this step, secure at one point.
DIN Rail Mounting Adaptor
M•RESTER
2. DIN RAIL MOUNTING
Set the base socket so that its mounting slider is at the bot-
tom. Position the upper hook at the rear side of base socket
on the DIN rail and push in the lower. When removing the
socket, push down the mounting slider utilizing a minus
screwdriver and pull.
DIN Rail Mounting Slider
35 mm wide
DIN Rail
3. GROUNDING
Secure the mounting bracket at the other point with the
other screw. In this step, secure the grounding wire togeth-
er with the screw.
M•RESTER
Solderless Te r
minal
• MOUNTING REQUIREMENTS unit: mm (inch)
8.5
(.33)
[3.3 (.13)]
DIN RAIL
35mm wide
80 (3.15)
45 (1.77)
4
(.18)
2–M4 MOUNTING SCREW
(used as ground terminal (G))

MDP-LC
EM-8128 Rev.10 P. 3 / 3
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
TERMINAL CONNECTION
Connect the unit as in the diagram below.
Be sure to cross-wire between the Ground terminal (G) and that of the protected equipment. When the surge protector is
connected with a device which has no ground terminal (See figure below), ground the M-RESTER Ground terminal (G) only.
M-RESTER
6
7
1
2
M-RESTER
5
1
2
6
7
8
3 3
8
(PROTECTED EQUIPMENT)
9
44
9
STRAIN GAUGE
XMTR
SHIELDED WIRE
–
+
–
+
G
–
+
OUTPUT
V
U
POWER
EXC.
INPUT
10 5
G
STRAIN GAUGE
EXC.
OUTPUT
■GROUNDING
M-RESTER PROTECTED
EQUIPMENT
G
G
CROSSOVER WIRE
GROUNDING
(100 ohms or less)
A crossover wire between M-RESTER ground and the ground or
metallic housing of the equipment is required for protection.
If the protected equipment has no ground terminal, ground the
M-RESTER only.
When the M-RESTER is mounted with DIN Rail Mounting Adapter,
connect the grounding wire to the mounting screw of the M-RESTER.
WIRING INSTRUCTIONS
■SCREW TERMINAL
Torque: 0.8 N·m
MAINTENANCE
Check surge protectors periodically. Many cases of light-
ning are ignored, and even lightning at a far distance often
causes inductive surges.
We recommend that you check your surge protector about
twice a year, before and after the rainy season. Check
whenever you experience a strong lightning occurrence.
Checking procedure is explained in the following:
■CHECKING
WIRING
1) Make sure that wiring is done as instructed in the con-
nection diagram.
2) Make sure that the Ground terminal (G) is connected to
the metallic housing of protected equipment.
3) Make sure that the Ground terminal (G) is grounded to
earth.
DISCHARGE FUNCTION
1) Remove all wiring connected to the surge protector when
you test the element module.
2) Apply 15V DC across the terminals (+) – (–) and check
leakage current. The meter shows ≤ 2µA.
Apply 1mA DC current and measure voltage across the
same terminals. The meter shows ≤ 25V DC.
3) Apply ±15V DC across the following terminals and check
leakage current. The meter shows ≤ ±2µA.
Apply ±1mA DC current and measure voltage across the
same terminals. The meter shows ≤ ±25V DC.
Terminals (–) – (G), (L2) – (G)
4) Apply ±0.3V DC across the terminals (L1) – (L2) and
check leakage current. The meter shows ≤ ±0.1µA.
Apply ±1mA DC current and measure voltage across the
same terminals. The meter shows ≤ ±3V DC.
5) If a DC voltage source is unavailable, check resistance
across the following terminals on the high resistance
range of multimeter (measuring current ≤ 0.25µA) and
confirm no conduction. The meter shows ≥ 1MΩ at (L1) –
(L2), ≥ 10MΩ at other terminals. When measuring across
(+) – (–), connect the probes so that positive voltage is
applied to (+) terminal.
Terminals (L1) – (L2), (+) – (–), (L2) – (G), (–) – (G)
6) Confirm conduction across the same terminals with a
500V DC 1000MΩ insulation tester (The tester shows ≤
20MΩ).
If any of the above tests shows negative, replace the pro-
tector.