What does "MMA" and "MSA" generally stand for?

[Ron247]

I have seen these 2 abbreviations on Electrical drawings several times but have not seen what they stand for noted in a legend or abbreviations table. I am assuming they are so obvious in the Electrical world they may not need to be stated, but I am structural. I also see UGPS stated and not defined but that appears to be UnderGround Power Supply.

 

[MacGyverS2000]

Context matters... can you provide an example?

Dan - Owner

http://www.Hi-TecDesigns.com

 

[Ron247]

Here are 3 different places from the E drawings. If the MSA stands for Main Distribution Board as written next to it, it is the worse acronym in history.

 

[dpc]

They are site specific names. Not sure what the intent was, Main Switchboard? idk. But they aren't industry standards or conventions.

 

[itsmoked]

The fact that they put them in quotes seems to back up dpc's point. It also seems they'd have to put their "quoted" definition on the margin of the drawing somewhere, maybe the Key?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Ron247]

I have looked everywhere and the drawings can be searched in most locations. If the key is in a jpg or png type insert, it will not generally search.

I still looked at the legends and abbreviations. Oddly, I saw these in a Texas job and a CA job. I understand a really local definition by someone, but 2 states in 4 months. That is why I though they were an industry standard I could not find.

The "MSA" next to Main Distribution Board to me would indicate it is the abbreviation for it but it makes no sense. And whey isn't the word "abbreviation" shorter? Seems it should but it has 8 different abbreviations.

MM could easily be Main Meter but what is the A?

 

[che12345]

Dear Mr.Ron247 (Structural)(OP)5 Nov 21 13:59
"... I have seen these 2 abbreviations .... several times but have not seen what they stand for noted in a legend or abbreviations table. I am assuming they are so obvious ... they may not need to be stated, but I am structural. I also see UGPS stated and not defined but that appears to be UnderGround Power Supply."
1. Many switchboard manufacturers have their own ways for identification e.g. for (location by symbol =, - etc. ); (high voltage boards by MHA, MHB ... etc.); (low voltage MSA, MSB...etc. ), (metering HM, MMA, MMB...etc.), (grounding MGA, MGB ...etc.). These are NOT IEC or ANSI standards.
2. For the structural, refer to the Floor plan; where the location and the name (e.g. "MSA" is located.
3. The project may comprising of "MMA...", + "MHA..." + "MSA..." ... etc.
3.1. For detail of say "MSA", refer to "MSA" drawing which may comprising of dimension, single-line, schematic wiring diagram etc.
Che Kuan Yau (Singapore)

 

[davidbeach]

MSA is the equipment that wears a nameplate that says “MSA”. That’s to make sure you don’t confuse it with MSB.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[waross]

WAG
Main Meter, and Main Switch? If they do an expansion then look for MMB and MSB.


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[LittleInch]

If you look closely it seems to be showing you what is contained within each cubicle inside the boxes with a long dash and two short dashes.

The location plan defines the physical box.

I would go for Master Meter A
Metered Supply A
I think you're right about the power supply.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[waross]

Another WAG
Main Meter Assembly?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[waross]

The meaning may be clarified in the contract specifications.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Ron247]

The Main Meter A, Main Meter B, Main Meter C system makes sense, but I find it hard to call more than one thing "Main".

 

[LittleInch]

But the main metre is 4000A and then there are House meters at 100A, so it's a lot bigger.

I have no problem in having several main meter when there are smaller meters downstream.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.