Model-TAC-L

Supported Applications

The Dwyer Model TAC-L is a portable digital tachometer designed to measure rotational speed (RPM) and surface speed. It operates in two modes: non-contact measurement using a laser photo sensor that detects reflections from the target, or contact measurement by applying a rotatable head directly to the shaft of an object.

For low RPM values measured with the non-contact laser method, accuracy is improved when multiple reflective marks are attached at average distances apart on the rotating object. The user must divide the displayed reading by the number of reflective marks to determine the true RPM.

Operating Conditions & Performance

The Model TAC-L operates within an ambient temperature range of 32 to 122°F (0 to 50°C). It features a sampling time of 0.8 s and delivers an accuracy of ±(0.05% + 1 digit) across its measurement ranges.

Measurement capabilities include:

• Non-contact (RPM): 2.5 to 99,999 RPM with a measuring distance range of 2 to 20" (5 to 50 cm).
• Contact (RPM): 0.5 to 19,999 RPM.
• Surface speed: 0.05 to 1999.9 m/min.

The unit is powered by four 1.5 V AA alkaline batteries (not provided) and features a backlit LCD display with five digits, seven segments, and a height of 0.7" (1.8 cm). Recorded data resets each time the measuring button is pressed.

Configuration Options

The Model TAC-L series includes specific accessories to support different measurement scenarios:

• Contact Rotational Heads: Three heads are supplied. The large tapered and pillar rubber pieces are suitable for low speed, while the small tapered piece is suitable for high speed.
• Contact Surface Wheel: Included for surface speed measurements.
• Housing & Display: Constructed from strong, lightweight ABS plastic designed to fit comfortably in the hand. The large LCD includes a backlight for use in dark areas.
• Casing: A protective carrying case is supplied with the model.

An optional NIST traceable calibration certificate (NISTCAL-EL1) is available.

Key Product Differences

The series consists of a single base configuration, Model TAC-L. The device supports both contact and non-contact measurement methods within the same unit. No field service or repair should be attempted by the user; units requiring repair must be returned to avoid voiding the warranty.