MNM MS-5K / MS-520 DIY Floor & Platform Scale Guide: Wiring, RS-232 & Setup

pete8781
Jul 30
2 min read

Phone: (832) 290-3120

Email: mnmscales@yahoo.com

Contact MNM Scales with your planned platform size, target capacity and environment so they can confirm the exact kit configuration before fabrication.

MNM MS-5K / MS-520 DIY Floor & Platform Scale Guide

The MNM MS-5K/MS-520 kit is sold specifically for people building a floor or platform scale without purchasing a complete deck. That makes frame design and load transfer just as important as the electronics: a strong platform can still weigh poorly if it rocks, binds or transfers part of the load around the sensors.

Design the deck around the load path

Place sensor supports where the deck can transfer weight without excessive flex. The frame should be rigid enough to keep the load cells aligned but should not lock the supports against normal load-cell deflection. Account for the deck’s own dead weight, off-center loads, carts/pallets rolling onto the deck and impact. Do not rate the finished platform simply by summing load-cell nameplates.

Cable and junction layout

MNM emphasizes high-visibility silicon-coated orange cable. Protect it anyway: run cable away from pallet-jack wheels, forklifts, sharp frame holes and motor/VFD power wiring. Use strain relief and leave service slack at moving or adjustable points. Keep junctions accessible for troubleshooting but protected from water and physical damage.

Leveling and corner consistency

A multi-support platform should sit firmly with all load points engaged. After assembly, test the same known load near each corner/support. Correct mechanical rocking first. If the junction hardware supports corner trimming, use that only after the structure is sound, then complete the overall zero/span calibration.

Connecting MS-520 RS-232 to a PC or logger

Confirm the physical serial connector and pinout on the exact indicator.
Obtain baud rate, parity/data bits and output format for the shipped MS-520 revision.
Use a compatible RS-232 port or an appropriate USB-to-serial adapter.
Capture raw output in a terminal program first; only then build spreadsheet, database or custom software parsing around the verified data string.

Calibration and acceptance testing

After the finished deck is installed, zero the empty scale, apply a known calibration load, verify multiple positions and loads, then repeat after unloading. Check the scale again after it has been used under normal carts, pallets or containers. A DIY platform should not be considered finished until both structure and weighing performance are verified.

Read the complete MS-5K/MS-520 guide

FAQ

Can I make any platform size? The kit can be integrated into custom structures, but platform dimensions change bending, corner loading and structure requirements. Confirm the design for the intended load.

Is RS-232 the same as USB? No. A modern computer may require a USB-to-RS-232 adapter plus correct serial settings.

Can I use the kit in a warehouse? MNM markets it for floor/platform applications, but the deck, load rating, traffic protection and environment must be engineered for warehouse use.