GE Multilin MM300 Operating instructions

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MM300 Installation
Recommendations
Title Name Signature Date
Prepared By Eider Brazal 11 Oct 2019
Revised By Jokin Galletero 14 Oct 2019

Page 2 of 15
GE Grid Solutions
Grid Automation
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48170 Zamudio
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Contents:
1. INTRODUCTION ....................................................................................................................................................3
2. MM300 PERFORMANCE .......................................................................................................................................3
2.1. HARDWARE ........................................................................................................................................................... 3
2.2. RELIABILITY ............................................................................................................................................................ 4
2.3. WARRANTY ........................................................................................................................................................... 5
3. MECHANICAL RECOMMENDATIONS .....................................................................................................................6
4. THERMAL RECOMMENDATIONS ......................................................................................................................... 13
5. ELECTRICAL RECOMMENDATIONS ...................................................................................................................... 18

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GE Grid Solutions
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1. INTRODUCTION
The MM300 is a modular motor protection and control system designed specifically for low-voltage motor
applications. It was launched to the market in 2007.
The aim of this report is to provide recommendations for the installation of the MM300 relay that may be
considered to optimize motor protection reliability.
At the date of this report there are more than 37000 units supplied worldwide and installed in many
different applications and countries.
2. MM300 PERFORMANCE
2.1. Hardware
The MM300 is packaged in a modular arrangement.
Fig. 1 Relay base and expansion modules.
The base module consists of:
- Slot A: power supply.
- Slot B: CPU and communication module.
- Slot C: IO_C Vac Inputs/Outputs module or IO_E Vdc Inputs/Outputs module.
- Slot D: IO_A CT module.

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The expansion module is configurable and different modules can be ordered for slots E, F, G and H:
Fig. 2 Expansion modules options.
2.2. Reliability
The MTBF (Mean Time Between Failures) is 505 years as of April 3, 2019 latest recorded figures.
This is equivalent to a failure rate of:
FR = 1 / MTBF = 1 / 505= 0.20 %/year
This performance has been constant since that date due product maturity and our continuous
improvement program.

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2.3. Warranty
Fig.3 Ten years warranty logo in the web.
GE guaranties all MM300 supplied since October 1st, 2013 for 10 years as the rest of protection and control
products that are in active life cycle status.
This warranty includes materials and workmanship when the product is wired, set and connected as per
the instruction manual and within the published specifications.
This extended warranty has been possible as a result of many product and process improvements in the last
10 years using modern techniques of product design, manufacturing, components selection and field returns
continuous improvement.
To achieve the best performance, cybersecurity, etc. GE publishes periodically new firmware versions with
the corresponding release notes that customers may download and upgrade at no charge in the field if they
feel the new version provides significant advantages.

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3. MECHANICAL RECOMMENDATIONS
In order to ensure good connection of the boards, please follow recommendations below:
1- Cable harnesses must not be too tight.
Fig. 4 Example of a proper wiring.
This allows good connection between the boards and the internal bus board of the relay.

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It also avoids damaged connectors as per the pictures below:
Fig. 5 Example of broken connector.
And avoids sagged pins in the boards:
Fig. 6 Example of sagged pin.

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Cards screw properly inserted.
Fig. 7 Screws properly inserted.

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2- Do not use big, flat head nor electric screwdrivers. Use only small manual Philips screwdriver.
Fig. 8 Use only small manual Philips screwdriver.
This is an example of a relay case damaged due to excessive screw tightening.

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Fig. 9 Relay case damaged due to excessive screw tightening.
Maximum tightening torque is 10lb.in.C as per the instruction manual. As the screw is made of steel
and the relay case is plastic, it has low tightening torque. Therefore, manual small Philips
screwdriver is recommended.
Fig. 10 Maximum tightening torque specified in the instruction manual.
3- The MM300 motor Protection series has been designed to be installed in compact drawers in harsh
industrial environments.