Mebay GM50H MK3 User manual

GM50H MK3
ENGINE METER
USER MANUAL

GM50H MK3 ENGINE METER USER MANUAL
1
Software Version
No.
Version
Date
Note
1
V1.0
2020-11-11
Original release.
Chongqing Mebay Technology Co.,Ltd
Add: No6-2,Building 4, Gangan Rd, Jiangbei District, Chongqing.
Tel：[phone]
Fax：[phone]
Web：http://www.mebay.cn
http://www.cqmb.cn
E_mail：[email protected]

GM50H MK3 ENGINE METER USER MANUAL
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Symbol Description
Symbol
Description
Note
Remind operators to operate correctly, otherwise it may cause
the equipment not to work correctly.
Be care
It is indicated that potential hazards can damage equipment
without proper precautions.
Warning
It is indicated if appropriate preventive measures are not taken,
potentially dangerous situations may result in death, serious
personal injury or significant property losses.

GM50H MK3 ENGINE METER USER MANUAL
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Warning
1. The installation of this equipment must be carried out by professionals.
2. When installing and operating the meter, please read the entire instruction manual
first.
3. Any maintenance and commissioning of the equipment must be familiar with all the
equipment.
4. t, safety standards and precautions in advance, otherwise it may cause personal
injury or damage to related equipment.
5. The engine must have an overspeed protection device independent of the meter
system to avoid casualties or other damage caused by engine out of control.
6. After the installation of the meter is completed, please verify that all protection
functions are valid.
Be Care
1. Please keep the good connection of the power supply of the meter. Do not share
the connection lines of the positive and negative electrodes of the battery with the
floating charger.
2. During the operation of the engine, do not disconnect the battery, otherwise it may
cause damage to the meter.

GM50H MK3 ENGINE METER USER MANUAL
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CATALOGUE
1. Summary ............................................................................................................. 5
2. Main Features ...................................................................................................... 5
3. Parameters Display .............................................................................................. 5
4. Protection .............................................................................................................5
5. Parameters .......................................................................................................... 6
6. Overall Dimension and Wiring Diagram ................................................................ 6
7. Installation instruction ...........................................................................................9
8. Panel and display ............................................................................................... 10
9. Warnings and Shutdown Alarms .........................................................................12
10. Parameters setting ........................................................................................... 13
11. Fault finding ..................................................................................................... 15
Notes:
1. All rights reserved. No part of this duplication may be reproduced in any material
form (including photocopying or storing in any medium by electronic means or others)
without the written permission of the copyright holder.
2. MEBAY Technology reserves the rights to change the contents of this document
without prior notice.

GM50H MK3 ENGINE METER USER MANUAL
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1. Summary
GM50H MK3 is one light and low price-orientated module used for
demonstrating engine RPM,coolant temperature, oil temperature,oil pressure, battery
voltage and Hours. The users can adjust and set the parameters by the button on the
front face in order to meet the different requests.
Besides, it uses the European-style terminals for connection which is more
convenient for installation and detachment.
2. Main Features
There are two models for GM50H MK3 series Meter:
GM50H MK3: monitor and display RPM, Oil Pressure, coolant temperature, oil
temperature, Battery voltage and Accumulation Time with Alarm function added.
GM50HR MK3: Based on the functions of GM50H MK3, RS485 Port is added to
support MODBUS Protocol.
32bit high performance single chip microcomputer.
5 screens high-light digital tube can demonstrate the parameters.
Various kinds of protections.
Input frequency is available to check RPM.
Variety of sensor curves' parameters is set inside.
Sensor curve can be self-defined by buttons.
It has three analog input channels of sensors, among which the oil pressure
sensor is compatible with voltage signal input;
The parameters can be set and adjusted by the button on the front face.
With RS485 port, remote data monitoring can be realized by using Modbus
Protocol (only GM50HR has it);
It has high current alarm relay, one normally open and one normally closed output,
which is convenient for users to use;
Standard coolant-proof rubber gasket. The coolantproof can reach IP54.
All the connections are adapted with European connectors so that installation,
connection, repair and replacement can be more easily.
3. Parameters Display
Engine speed
Engine oil pressure
Engine coolant temperature
Engine oil temperature
Engine battery voltage
Total running time
4. Protection
Over speed
Low oil pressure
High coolant temperature
High oil temperature
Sensor open
Battery under voltage warning

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5. Parameters
Options
Parameters
Working voltage
DC8V----36V Continuous
Power consumption
Standby：24V：MAX 1W
Working：24V：MAX 1.5W
AC Voltage Input
1P2W 50VAC-280VAC（45～70Hz）
Rotate speed sensor
Frequency
50-10000Hz(AC3～65V)
MAX Accumulating Time
99999.9Hours（Min storage time:6min）
Relay Output
5AMP Non-contact normal open & normal close output
Working condition
-25-65℃
Storage condition
-40-85℃
Protection Level
IP54：when coolantproof rubber gasket is added between
meter and its panel
Insulation strength
Apply AC2.2kV voltage between high voltage terminal and
low voltage terminal; The leakage current is not more than
3mA within 1min.
Overall dimension
100mm*100mm*77mm
Panel cutout
91mm*91mm
Weight
0.15Kg
6. Overall Dimension and Wiring Diagram
Overall Dimension:
100
100
顶视图
Top view
100
90
100
90
底视图
Bottom view

GM50H MK3 ENGINE METER USER MANUAL
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90
100
88
68
9
左视图
Left view
100
90
959
88
Descriptions of terminal connection
No.
Function
Description
Cable cross
sectional area
1
Battery Negative Input B-
meter power supply input B-.
1.5mm2
2
Battery Negative Input B+
meter power supply input B+.
1.5mm2
3
Oil pressure sensor
Connect sensor input.
1.0mm2
4
Temperature Sensor
1.0mm2
5
Oil temperature sensor
1.0mm2
6
Sensor common GND
Connect the battery negative or outer.
1.0mm2
7
Speed sensor +
Use a shielded wire to connect the
speed sensor.
1.0mm2
8
Speed sensor -
1.0mm2
9
RS485 B
A 120 Ω shielded wire and good
1.0mm2

GM50H MK3 ENGINE METER USER MANUAL
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grounding are recommended.
10
RS485 A
1.0mm2
11
RS485 SCR
1.0mm2
12
+5V Output
Connect the power supply of the oil
pressure sensor with the output voltage
signal, with a maximum of 50mA.
1.0mm2
13
Reserved
14
AC Voltage L
Connected to the generator set output L
phase.
1.0mm2
15
AC Voltage N
Connected to the generator set output
N.
1.0mm2
16
Alarm relay Normal close
Passive Output, Max 5Amp.
1.5mm2
17
Alarm relay Normal open
1.5mm2
18
Alarm relay Common
1.5mm2
GM50H MK3 typical Wiring Diagram
1 2 3 4 5 6
-+
GEN VOLTS ALARM OUTPUT
OIL PRESSURE
COOLANT TEMP.
OIL TEMP.
DC8-36V
78
+-
MPU
R/U
9 10 16 17 18
NC NO
COM
11
RS485
B A SCR
12
+5V
OUTPUT
13 14 15
N
L
GM50H MK3 / GM50HR MK3
Note: Please don’t move during running status or it may cause the meter
broken!

GM50H MK3 ENGINE METER USER MANUAL
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7. Installation instruction
The meter is fixed by two special fixing members and screws, and the screws of
the metal fasteners cannot be too tight.
Panel Cutout: W91mm*H91mm.
91
91
开孔尺寸
Opening size
Note: If the meter is installed directly in the genset shell or other fluctuated
equipment, the rubber pad must be installed
.
Battery Voltage Input
GM50H MK3 is suitable for 8-36V DC battery voltage. Battery negative must be
reliably connected to the enclosure of the engine. The meter power supply B+ and B-
must be connected to battery positive and negative, and the wire size must not be
less than 1.5mm2.
NOTE:
In case of floating charger connect charger output to battery positive and negative
directly, then, connect battery positive and negative poles to meter positive and
negative power supply.
Output and relay expansion
Note: All outputs of the meter are relay contacts. The maximum current
capacity is described in the "Parameters" in this manual. Please use it in the relay
current capacity. If an extended relay is needed, add a continuous current diode
(when the extended relay coil is DC) or a resistance-capacitance loop (when the
extended relay coil is AC) to both ends of the coil to prevent interference with the
meter or other equipment.

GM50H MK3 ENGINE METER USER MANUAL
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Withstanding voltage test
If withstanding voltage test is conducted after the meter has already been
installed onto the control panel, please unplug all meter terminal connections in order
to prevent high voltage from damaging it.
8. Panel and display
ICON
NAME
Meaning
Engine speed
The LED screen displays the engine speed in RPM.
Engine oil pressure
The LED screen displays the engine oil pressure in kPa.
Engine coolant
temperature
The LED screen shows the cooling coolant temperature
of the engine in centigrade ℃.
Oil temperature
The LED screen shows the oil temperature of the engine
in centigrade ℃.
Battery voltage
The LED screen displays the battery voltage of the
engine in volts.
Total running time
The LED screen displays the accumulated working time
of the engine in hours H.
Key Function Description
KEYS
NAME
Main Function
Setting
Press for 4 seconds to enter the parameter setting mode.
In the parameter browsing interface of setting mode, press
to enter the parameter modification interface.
In the parameter browsing interface of setting mode, press
to enter the parameter modification interface.
+
Under display mode, parts of the page can move up.
Under edition mode, pressing this key to move the digit or
increase the numbers.
In the display mode, the coolant temperature and oil
temperature change pages.
Oil pressure
Coolant temp
&Oil Temp.
Battery volt
Total time
Engine speed
Public alarm
Setting
Value Dec
Value Inc

GM50H MK3 ENGINE METER USER MANUAL
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-
Under display mode, parts of the page can move down.
Under edition mode, pressing this key to move the digit or
decrease the numbers.
In the display mode, the coolant temperature and oil
temperature change pages.
+
Custom
sensor curve
Press the PROG and + together for more than 4 seconds,
can enter the sensor parameter setting interface.
+
Check the
software
version
Press PROG key and - key together to check the software
version of the meter.
+
LED Test
Test if all LED lights are ok, pressing this key to test if all
lighted, all off when loosen it.
+
+
Restore
default
Press PROG key, + key and - key together,then all the
parameters can be set as defaults.
Work flow chart
Note: within the safety delay time, only the overspeed alarm will be responded,
and other alarms will not respond.

GM50H MK3 ENGINE METER USER MANUAL
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9. Warnings and Shutdown Alarms
Warnings
Notes: Warning is a non-serious failure state, which will not harm the engine
system for the time being. It only reminds operators to pay attention to the situation
that does not meet the requirements and solve it in time to ensure the continuous
operation of the system. When the warning occurs, the engine does not stop. Once
the fault is removed, the warning is automatically canceled.
Under battery voltage warning
When the meter detects that the battery voltage is lower than the "Under battery
voltage warning", Then start warning delay and the duration (Normal alarm delay)
have not returned to normal, the warning of Under battery voltage warning is reported.
lights will light up, bettery display flashing.
Shutdown Alarms
Warning: After the Shutdown Alarm occurs, the system will be locked
immediately and the engine will be stopped. Only after troubleshooting, press
key to clear the alarm, can it be re-operated.
Notes：When the shutdown alarm failure occurs, the "ALARM" lights will light
up and the engine automatically stops.
Over speed alarm
When the meter detects that the engine speed is higher than “Over speed alarm”,
Then start alarm delay and the duration (Emergency delay) have not returned to
normal, the alarm of over speed is reported.The alarm light flashes, the
speed display screen locks the alarm speed value, and the alarm relay outputs.
Low oil pressure alarm
When the meter detects that the engine oil pressure is lower than “Low oil pressure
alarm”, Then start alarm delay and the duration (Normal alarm delay) have not
returned to normal, the alarm of low oil pressure is reported.The alarm light
flashes, the oil pressure display screen locks the alarm oil pressure value, and the
alarm relay outputs.
High coolant temperature sensor alarm
When the meter detects that the coolant temperature value is higher than the "High
coolant temperature alarm", Then start alarm delay and the duration (Normal alarm
delay) have not returned to normal, the alarm of High coolant temperature alarm is
reported. The alarm light flashes, the coolant temperature display screen locks
the alarm coolant temperature value, and the alarm relay outputs.

GM50H MK3 ENGINE METER USER MANUAL
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Oil pressure sensor disconnected alarm
When the oil pressure sensor is detected to be disconnected,Then start alarm delay
and the duration (Normal alarm delay) have not returned to normal, the alarm of Oil
pressure sensor disconnected alarm is reported. The alarm light flashes,the oil
pressure display shows "---" and flashes.
Coolant temperature sensor disconnected alarm
When the coolant temperature sensor is detected to be disconnected,Then start
alarm delay and the duration (Normal alarm delay) have not returned to normal, the
alarm of coolant temperature sensor disconnected alarm is reported. The alarm light
flashes,the coolant temperature display shows "---" and flashes.
10. Parameters setting
Enter the edition page
Please set the parameters according to below steps:
1)Press for 4 sec, loose it when “P-00”displayed, which means system
comes into setting page and display the first option.
2)Press or to choose the options and press to set. Press
or again to set the right value. Then press to revert back to last
layer and press again for more than 4 sec to save the value.
3)Press and simultaneously for more than 4sec: when “nu.1” is
displayed, it means system comes into curve setting page. Press or
to choose the curve needed to be modified (1-Oil pressure,2-coolant
temperature,3-oil temperature).Then press to set, choose the value of
resistance(A) and sensor value(d) by pressing or ,press again
to set. Then press to revert back to last layer and press and for
more than 4 sec to save the value.
4) Resistance input data: from min to max.
Note: after the parameter is modified, it will take effect immediately!
Parameter setting
Code
Parameter
Range(defaults)
Notes
P00
Flywheel teeth
0-300(0)
If the setting is 0, RPM sensor
Disabled, then RPM is resulted by
Hz.
P01
Gens poles
0:2
1:4
2:6
3:8
When the flywheel teeth is set as
0,the RPM will be resulted by
frequency.
Pole 2: 50Hz---3000RPM.
Pole 4: 50Hz---1500RPM.
Pole 6: 50Hz---1000RPM.
Pole 8: 50Hz---750RPM.

GM50H MK3 ENGINE METER USER MANUAL
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P02
Oil pressure
sensor
0: Disabled
1: VD0 0-10bar
2: MEBAY-003B
3: SGH
4: SGD
5: SGX
6: CURTIS
7: DATCON 10Bar
8: VOLVO_EC
9: 3015237 10Bar
10: WEICHAI 0-6Bar
11: ZYDQ 0-8Bar
12: SIQIANG 0-10Bar
13: User defined-Resistance
14: Volt In 1MPa-0-5V
15: Volt In 1MPa-0.5-4.5V
16: User defined-Voltage
17: Normally closed oil
pressure alarm switch
Choose the usual oil pressure
sensor, if the sensor users choose
is not these types, it can be User-
defined.
P03
Coolant
temperature
sensor
0: Disabled
1: VD0 40 ℃ -120 ℃
2: MEBAY-001B
3: SGH
4: SGD
5: SGX
6: CURTIS
7: DATCON
8: VOLVO_EC
9: 3015238
10: PT100
11:MEBAY-Mier
12: WEICHAI 40-120℃
13: CC073 25-125℃
14: SIQIANG 30-120℃
15: Self-defined
Choose the usual coolant
temperature sensor, if the sensor
users choose is not these types, it
can be User-defined.
P04
Oil temperature
sensor
0:Disabled
1:VD0 40 ℃ -120 ℃
2:MEBAY-001B
3:SGH
4:SGD
5:SGX
6:CURTIS
7:DATCON
8:VOLVO_EC
9:3015238
10:PT100
11:MEBAY-Mier
12:WEICHAI 40-120℃
13:CC073 25-125℃
14:SIQIANG 30-120℃
Choose the usual oil temperature
sensor, if the sensor users choose
is not these types, it can be User-
defined.

GM50H MK3 ENGINE METER USER MANUAL
15
15:Self-defined
P05
Over speed
alarm
0-6000RPM
(1650RPM)
if the value is set as 6000, then the
over speed alarm is disabled.
P06
Over speed
delay
0.0-5S(0.5S)
When the engine speed is higher
than the preset value, it is regarded
as over speed.
P07
Low oil pressure
alarm
0-500 KPA(100KPA)
if the value is set as 0, then the low
oil pressure alarm is disabled.
P08
High coolant
temperature
alarm
50-150℃(95 ℃ )
if the value is set as 150, then the
high coolant temperature alarm is
disabled.
P09
High oil
temperature
alarm
50-250℃(105 ℃ )
if the value is set as 250, then the
over speed alarm is disabled.
P10
Sensor alarm
delay
0.5-15.0S(5.0S)
Sensor alarm delay.
P11
Under battery
voltage warning
8.0-36.0V(9.0V)
if the value is set as 5, then the
under battery voltage is disabled.
P12
Page-change
delay
1.0-120.0S(5.0S)
Interval time for coolant
temperature and oil temperature,
the max time is manually change.
P13
RPM
for start success
200-1000RPM
(600RPM)
When the RPM is over than the
pre-set value once on power, then
it is regarded that engine crank
successfully.
P14
Oil Pressure
for start success
138-412KPA
(206KPA)
When the oil pressure is over than
the pre-set value once on power,
then it is regarded that engine
crank successfully.
P15
Safety delay
3-300S(10S)
Low oil pressure, high coolant
temperature, high oil
temperature, Under battery
voltage are all invalid during this
time except for over speed.
P16
Alarm output
time
0~120S(30S)
Alarm relay output setting.
0:alarm output disabled;
120:alarm output all the time.
P17
RS485 ID
1-254(16)
RS485 ID setting,only for GM50HR
MK3.
P18
Alarm function
0:Disabled
1:Available
All the alarm indications and
outputs are forbidden if it is set
as 0.
11. Fault finding
Symptoms
Possible Solutions
Meter no response
with power
Check DC voltage.
Check DC fuse.
Check if the terminal 1 and 2 is with battery voltage.
Speed display error
Check whether the speed sensor is normal;
Check whether the number of teeth of the instrument flywheel is

GM50H MK3 ENGINE METER USER MANUAL
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set normally.
Oil pressure display
error
Check whether the oil pressure sensor is normal;
Check the wiring of oil pressure sensor;
Check whether the common ground wire of the sensor is well
connected to the negative pole of the battery;
Check whether the oil pressure sensor type parameters
selected by the instrument are consistent with the actual use.
Coolant temperature
display
error
Check whether the coolant temperature sensor is normal;
Check the wiring of coolant temperature sensor;
Check whether the common ground wire of the sensor is well
connected to the negative pole of the battery;
Check whether the type parameters of coolant temperature
sensor selected by the instrument are consistent with the actual
use.
Engine shutdown
Check whether the engine temperature is too high;
Check whether the engine oil pressure is too low;
Check the alternator voltage;
Check whether the fuel circuit of the engine is normal.
Low oil pressure alarm
Check oil pressure sensor and its wiring.
Check the oil pressure sensor type and meter settings must be
consistent.
Check whether the low oil pressure sensor is normal.
High coolant
temperature alarm
Check coolant temperature sensor and its wiring.
Check the coolant temperature sensor type and meter settings
must be consistent.
Check whether the temperature sensor is normal.
Shutdown Alarm in
running
Find the fault according to the LED display information.
The meter does not
alarm
The instrument does not alarm
Check whether the rotating speed is normal;
Check whether the oil pressure is normal;
Check that the alarm value is set correctly and whether the
corresponding alarm function is enabled.
RS485 cannot
communicate normally
Check the connection.
Check if the communication ID number setting is correct.
Check if the A and B lines of RS485 are reversed.
Check if the RS485 communication line driver is installed or not.
Check if the communication port of the PC is damaged.
Add a 120 Ω resistor between the AB of the meter RS485.