Scales let you capture package weight directly from a USB scale during shipping. Warehance reads the weight in real time and uses it for carrier rating and label creation, reducing manual entry and errors.
Prerequisites
- A USB HID-compatible scale (e.g., Dymo, Mettler Toledo, or models with "scale" in the product name)
- The scale connected to the same computer where you run Warehance
- QZ Tray installed and running (required for Warehance to communicate with the scale)
Step 1: Install QZ Tray
QZ Tray is a small desktop application that lets Warehance access hardware like scales and printers.
- Download QZ Tray from qz.io/download.
- Install it for your operating system (Windows, macOS, or Linux).
- Ensure QZ Tray is running before you use Warehance. It usually starts with your computer or stays in the system tray.
If Warehance prompts you to install QZ Tray, use that link or visit qz.io/download. After installing, refresh the Warehance page.
Step 2: Connect Your Scale
- Plug your USB scale into the computer.
- Turn the scale on and wait for it to stabilize.
- Ensure no other application is actively using the scale.
Step 3: Select Your Scale in Warehance
- In the top navigation bar, click the scale icon (balance icon).
- In the Scale Settings modal, choose your scale from the Select weight scale dropdown.
- Click Save Changes.
The list shows scales that Warehance detects (devices with "scale" in the product name, or Mettler Toledo devices). If your scale does not appear, check that QZ Tray is running and the scale is connected.
Step 4: Use the Scale During Shipping
The weight editor appears when you ship orders—for example, in the Shipping flow or Single Order Shipping.
Lock and Unlock
- Unlocked (open lock icon): The scale is active. Weight updates live as you place or remove items on the scale.
- Locked (closed lock icon): The displayed weight is fixed. Use this when the weight is correct and you are ready to proceed (e.g., print a label).
Click the lock icon to toggle between locked and unlocked.
Manual Entry
When the scale is locked, you can click the edit (pen) icon to type a weight manually. Click Save when done.
Barcode Scan to Lock
You can scan a special barcode to lock the weight instead of clicking. Generate action barcodes from the bolt icon in the header. The weight-lock barcode (e.g., whaction_weight_lock) locks the current scale reading when scanned.
Step 5: Organization Settings (Optional)
Admins can adjust scale behavior in Settings → Shipping → General Settings:
| Setting | Description |
|---|---|
| Auto Lock Scale | When enabled, the scale automatically locks after processing shipping labels. |
| Hide Scale Lock/Unlock Controls | When enabled, the lock/unlock icon is hidden. The weight display remains visible, but users cannot toggle the scale on or off from the UI. |
Supported Scales
Warehance detects:
- Devices whose product name includes "scale"
- Mettler Toledo scales
If your scale is HID-compatible and not listed, it may still work. Use the scale icon to open Scale Settings and check if it appears in the dropdown.
Troubleshooting
- Scale not in the list: Ensure QZ Tray is running, the scale is connected and powered on, and no other app is using it. Try unplugging and reconnecting the scale.
- Weight not updating: Unlock the scale (open lock icon). If it stays locked, lock and unlock again.
- Wrong units: Warehance converts scale output to your organization’s weight unit (e.g., lb or oz). Check Settings → Organization for the weight unit.