SHIMPO DT-315A User Manual

DT-311A & DT-315A Stroboscope

Instruction Manual

Inspection/Standard Accessories

If upon delivery shipping damage is detected, do not operate the
unit. Notify shipping carrier immediately for damage claim

instructions. Refer to nameplate and record serial number for future
reference. Items included with the DT-311A/DT-315A are:

• (1) Handle

• (1) Flash tube removing tool

• (1) AC charger/adapter (Model 315A only)

Features and Benefits

Shimpo’s DT-311A and DT-315A stroboscopes/digital
tachometers incorporate the latest microprocessor technology for

visual inspection applications:

• Aluminum construction provides exceptional durability

DT-311A

• High polish and focused reflector eliminates “blind”
viewing areas

• External trigger allows unit to be automatically
synchronized with equipment

• Continuous duty cycle eliminates need to shut down for
cooling

• Phase shift allows visual analysis of rotating/recip r ocating
objects

• High accuracy ( ±0.01% of reading ) is ideal for QC
inspection and process control

• Synchronous output enables strobe to drive other strobes

• Flash timer control conserves flash tube life

DT-315A

Congratulations on your purchase of a Shimpo DT-311A or
DT-315A stroboscope/digital tachometer. We trust you will

enjoy many years of professional results from your Shimpo
product.

Please read the entire instruction manual thoroughly before
initial set-up and operation; the information contained herein

will aid you in operating your Shimpo stroboscope safely and
with excellent results.

If you have any questions regarding our product(s), call your
local Shimpo representative or contact Shimpo Instruments

directly for assistance.

Important Safety Instructions

Do not operate or store instrument in the following places:
explosive areas; near water , oil, dust, or chemicals; areas

where temperature is above 104°F (40°C).

Do not look at the emitted light for long periods
of time; it can be harmful to the eyes.

Do not disassemble or repair unit while in
operation.

Set-up

The DT-311A and DT-315A may be operated handheld or else
mounted on a tripod for added convenience.

T o mount the strobe on a tripod (or any other mounting surface),
use screw ¼ -20unc, length 8mm or shorter for the tripod screw

hole on the bottom.

1

4

2

3

1. LED display: Displays function and value

2. EXT: External mode indicator

3. INT: Internal mode indicator

OperationDisplay P anel

True RPM Measurement

Shimpo stroboscopes are DUAL function instruments that give
the operator the illusion of “stopped motion” where in actuality

the equipment under observation is in a moving state. By
adjusting the flash rate, equipment in motion appears to be

standing still. With a slight adjustment, movement can be viewed
in apparent slow motion, which enables the operator or observer

to study the process in action. All Shimpo stroboscopes can
measure rotational (RPM) or reciprocating (strokes per minute)

speeds with the same high precision as with an electronic digital
tachometer.

To measure true revolutions per minute (RPM):

1. “Mark” the object to be measured by either visually noting
an inherent distinguishing characteristic (such as a label,

scratch, etc.) or physically marking the object with a small
piece of tape, pencil mark, etc.

2. Firmly plug in power cord.

3. Turn power switch on.

4. Turn setter from highest FPM downward.

5. The true RPM can be noted once the action appears frozen
and the first single image of the “mark” appears (see chart

below and accompanying diagram for further explanation).

6. To verify RPM reading, press “÷ 2”; a single image should
appear again.

4. B-CH: Battery charge indicator (DT-315A only)

5. FPM: Flash per minute indicator

6. deg: Phase shift degree indicator

7. mSec: Millisecond delay time indicator

8. Signal switch:Switches the unit from the external mode
to the internal mode (and vice-versa)

9. Display mode switch: When unit is set to the external
mode, the strobe will switch to RPM (FPM)/deg/msec

each time “MODE” is depressed

RPM (FPM) Displays flashes per minute

External input 0-35,000 RPM (FPM)

deg Displays flash delay in degrees

msec Displays flash delay in msec

10. Setter: Changes the flashing rate

11. (x2) Switch: In the internal mode, pressing “x2”
doubles the flashing rate

Shaft Rotation Flashes Flashes/ Stopped
(RPM) (RPM) RPM Shaft Images

6,000 4 times 4

4,500 3 times 3

At 1,500 RPM

3,000 2 times 2

1,500 1 time 1

750 1/2 time 1

500 1/3 time 1

12. (+) Switch: In the internal mode,when object appears
to be standing still, pressing “+” will give the illusion

that the object is moving towards the rotating direction
at a speed of 1 rotation in 6 seconds

13. ( ÷2) Switch: In the internal mode, pressing “÷2” divides
the flashing rate by two

14. (-) Switch: In the internal mode, when object appears
to be standing still, pressing “-“ will give the illusion

that the object is moving in reverse at a speed of 1 rotation
in 6 seconds

15. Input and output connector:
PIN #1: +12V

PIN #2: Synch output signal
PIN #3: Input signal

PIN #4: 0V

16. Power cord (DT-311A) / AC adapter (DT-315A)

17. Power switch

Internal Triggering Mode

To operate the stroboscope in internal triggering mode:

1. Firmly plug in power cord.

2. Turn power switch on.

3. If internal indicator is not on, press “SIG”; the INT light
will then turn on.

4. Aim light beam at object under observation. The optimal
distance between the strobe and moving object is

approximately 2 feet.

5. Measure RPM by turning the setter to adjust the flashing
rate to the rotational speed of the object.

NOTE: To achieve a particular rate quickly, use the “x2” or
“÷2” switches and then the setter for fine tuning.

NOTE: Once the internal timer has expired, the strobe will stop
flashing and the display will flash rapidly. To restart the strobe,

turn power switch off, then on, and the cycle will repeat.