3M™Model 724 Work Station Monitor Instructions, introduces the design, test, installation and fault conditions of the monitor.
This manual describes the purpose and theory of operation of the 3M Model 724 Work Station Monitor, which monitors wrist‑strap grounding and work‑surface grounding for two operators. It explains how the device measures loop resistance using selectable test voltages and resistance limits.
Installation instructions cover both ground‑monitored and non‑ground‑monitored setups, wiring, required accessories, DIP‑switch alarm settings, and how to verify proper operation. Safety information, fault indications, and warranty terms are also included.
| Test Voltages | 9 V or 16 V |
|---|---|
| Resistance Limits | 10 MΩ or 35 MΩ (lower detection ≈1.5 MΩ) |
| Measurement Current | < 3 pA |
| Measurement Interval | ≈ 2.0 seconds |
The monitor provides selectable test voltages of 9 V or 16 V.
The device can be set to resistance limits of 10 MΩ or 35 MΩ, with a lower detection threshold of about 1.5 MΩ.
A high‑resistance condition lights the red “H” lamp and triggers an audible alarm.
A 3M™ 2380 Monitor/Table Mat Cord and a ground wire with ring terminal are required.