Scales

Recommended Hardware

The hardware requirements are divided into two categories: components for an individual production line that will get a scale, and setup hardware for initial configuration. Essembi can support other scale models in addition to the OHAUS Courier 5000; connect with an Essembi team member if you have questions about a specific model.

Installation Guide for Scales

Install Pi Case

The top of the case has pillars for transferring heat to the case from the chips, so the case works like a heat sink. Thermal paste should be placed above and below the copper heatsink, but not on the thermal pads.

Peel off stickers on both ends of the thermal pads. Apply the appropriately sized pads to the three specified chips (all three are black).
Apply thermal paste to the top of the processor, not so much that it will spill out when pressed down.
Apply the copper heatsink on the processor, and put a little bit more thermal paste on top.
Install the case screws.

Be aware of the USB 3 ports vs the slower USB 2 ports.

Flash the Micro SD Card

Prerequisites: download and install Raspberry Pi Imager if it is not already installed, and download and unzip the latest essembi-scale-pi.img file (named essembi-scale-pi-YYYY-MM-DD.img.zip).

Flashing Steps

Insert a blank Micro-SD card (it should have come with a micro to full-sized SD adapter) and verify it is visible in "This PC".
Run Raspberry Pi Imager.
Configure the first screen: Device = Raspberry Pi 4, OS = Use Custom (select the extracted .img file), Storage = the SDXC card / drive. Be VERY careful not to accidentally select your computer's hard drive.

Edit Settings, General

Uncheck "set hostname"
Set user / password
Set Locale to their time zone

Edit Settings, Services

Check "Enable SSH"
Set "Use Password Authentication" as the method
Save the settings

Complete the Flashing Process

When returned to the "would you like to apply" prompt, hit "Yes".
When the next prompt appears, click "Yes" again.
Do not remove the SD card during the process.
The writer will go through writing and verification steps which take 2-3 minutes.
When the completion prompt appears, click "Continue", after which it is safe to remove the SD card.

When the SD card is written, you should be able to plug it into a Pi and fire it up. The first time you boot it, it may reboot once or twice. Raspberry Pi boots based on newly receiving power, so if you shut it down, simply unplug and plug back in to boot it again.

Connect the Scale & Pi

Plug in the USB hub into the power.
Plug the scale into the hub and turn on its port.
Plug the hub into the Pi.
Plug the Pi's USB-C power supply in.

Program the Scale

The only setting you should have to change on the scale should be to set it in Mettler-Toledo Continuous mode.

Hold "Menu" to enter the menu
Hit "No" to go to the next option
Hit "Yes" to select the current option, go back to the parent menu, and go to the next option in the parent menu
Hit "Exit" to end the menu

Setting Mettler-Toledo Continuous Mode

Follow this menu path: Menu, Print, Assign, Mt.CO. Units can be changed on the scale by holding down the "Units" button to toggle between lbs, kg, and more.

Configuring Scale Sensors in Essembi

Scale devices are configured as sensors with Type = Weight on the line (Settings > Lines). Important weight-sensor settings include For Line Finishes (enables automatic container finishes from scale readings), For Incident Tracking (enables downtime detection when finishes stop occurring), Tare Weight (subtracted from the reading before posting net quantity), and the standard Finish Threshold / Incident Threshold / Line Configuration and Sensor Configuration Override settings shared with count sensors.

Weight finishes are posted individually by timestamp. App Production Automation finish rounding / interval grouping primarily applies to count-sensor finishes; see Edge Devices.

OHAUS Courier 5000, Not Registering Weight

If your OHAUS Courier 5000 is powering on but not displaying any weight when items are placed on the platform, work through the steps below in order, starting with the simplest fixes first.

Step 1: Basic Checks

Level the scale. Place it on a flat, stable surface and use the leveling feet and bubble level to confirm it is properly leveled.
Power cycle. Remove all weight from the platform, then hold the power button to turn the scale off. Turn it back on and allow it to sit empty for approximately 30 seconds.
Re-zero the display. Press the Zero/Tare button before placing any items on the platform.

Step 2: Check the "Data Transfer" Setting

If Data Transfer is turned ON, the scale may freeze and fail to register new weights. Go to Main Menu > Print, select Data Transfer, set it to OFF, press NO until you see END, press YES, then press EXIT to return home.

Step 3: Check the Zero Limit

The scale will not register weight if the display has drifted too far from its calibrated zero point. Make sure the platform is completely empty, then press the Zero button. If the scale is over its zero limit, remove all load, allow it to settle, and re-zero before testing again.

Step 4: Verify Unit Settings

Navigate to Menu > Units and confirm that your desired unit (lb, kg, etc.) is turned on.

Step 5: Recalibrate the Scale

Go to the Calibration Menu, run Zero Calibration with the platform empty, then run Span Calibration using a known reference weight.

Step 6: Physical Inspection

Check that the platform sits evenly on all four corners with nothing wedged underneath.
Inspect the cable connection between the platform base and the display head, reseat it if loose.
If none of the above steps resolve the issue, load cell damage may be the cause, which requires professional service.

Contact OHAUS Support

Phone: 1-800-526-0659. Hours: Monday to Friday, 8:00 AM to 5:00 PM EST. The Courier 5000 comes with a standard 2-year warranty; if the unit is relatively new, it may qualify for a free repair or replacement.

Troubleshooting: Incident Opens While the Line Is Still Running

Sometimes a scale-backed sensor will open a downtime incident even though product is still moving on the line. This usually means pulse is not receiving fresh weight / finish data, so the sensor looks idle past the Incident Threshold.

Most common causes: a loose USB connection from the scale to the Raspberry Pi, network / MQTT connectivity issues to the Essembi pulse host or cloud, Pi power / reboot issues, or an Incident Threshold that is too aggressive for legitimate gaps between containers.

Use the Throughput Summary report to review pulse readouts across sensors on the line, including packaging sensors upstream of the scale.