Not suitable if your primary real-time security is Microsoft Defender Antivirus, as the virus definitions are identical.
The security intelligence update version of the Microsoft Safety Scanner matches the version described in this web page.
Microsoft Safety Scanner only scans when manually triggered. Safety Scanner expires 10 days after being downloaded. To rerun a scan with the latest anti-malware definitions, download and run Safety Scanner again. We recommend that you always download the latest version of this tool before each scan.
Safety Scanner is a portable executable and doesn't appear in the Windows Start menu or as an icon on the desktop. Note where you saved this download.
If I remember correctly Microsoft Defender has Periodic Scanning.
If another antivirus product is installed and working correctly, Microsoft Defender Antivirus will disable itself. The Windows Security app will change the Virus & threat protection section to show status about the AV product, and provide a link to the product's configuration options.
Underneath any third party AV products, a new link will appear as Microsoft Defender Antivirus options. Clicking this link will expand to show the toggle that enables limited periodic scanning. Note that the limited periodic option is a toggle to enable or disable periodic scanning.
Sliding the switch to On will show the standard Microsoft Defender Antivirus options underneath the third party AV product. The limited periodic scanning option will appear at the bottom of the page.