HT INSTRUMENTS HT2234N Optical Digital Tachometer

PRELIMINARY AND SAFETY

This instrument conforms with safety Standard EN 61010-1 related to electronic measuring instruments. For your own safety and to avoid damaging the instrument follow the procedures described in this instruction manual and read carefully all notes preceded by this symbol.

When taking measurements:

• Avoid doing that in rooms where explosive gas, combustible gas, steam or excessive dust is present.
• Avoid doing that if you notice anomalous conditions such as breakages, deformations, fractures, leakages of battery liquid, blind display etc.

CAUTION: For your own safety as well as that of the apparatus you are recommended to follow the procedures described in this instruction manual and carefully read all the notes preceded by the symbol.

PRELIMINARY INSTRUCTION

• Only the accessories supplied with the instrument guarantee compliance with the safety standards. They must be in good conditions and must be replaced, if necessary, with identical models.
• Do not effect any measurement under conditions beyond the limits specified in chapter 7.
• Check that batteries have been placed correctly.

DURING USE

Carefully read the following recommendations and instructions:

CAUTION

• No compliance with the Warnings and/or Instructions may damage the apparatus and/or its components or injure the operator.
• If the symbol “” is displayed during use interrupt testing and replace batteries following the procedure described under paragraph 6.2.

AFTER USE

• When the measurements are completed switch OFF the instrument.
  • Remove batteries when the apparatus remains unused for long periods.

INSTRUMENT DESCRIPTION

The HT2234N meter performs the hereunder tests:

• RPM and RPS speed measures with and without contact
• m/min, ft/min and yd/min surface speed measures
• Events counter
• MAX/MIN/AVE functions

PREPARING TO USE

INITIAL

• This instrument has been checked mechanically and electrically prior to shipment. Every care has been taken to ensure that the instrument reaches you undamaged.
• However, it is wise to carry out a rapid check in order to detect any possible damage which might have been caused during transport. Should this be the case, immediately enter the usual claims with courier.
• Check the packaging contained according to packaging list reported in paragraph 7.3. In case of discrepancies contact the dealer.
• In the event of re-shipment of the equipment please follow the instructions reported in chapter 8.

SUPPLY VOLTAGE

• The instrument is battery supplied. It uses four battery model 1.5V AA UM3 type included in the packaging.
• When the batteries are low the symbol “” is displayed. To replace batteries follow the instructions indicated in chapter 6.2.

CALIBRATION

• The instrument fulfils the technical characteristics listed in this manual. The performance of the specifications are guaranteed for one year.

STORAGE

• In order to guarantee the accuracy of the measurements, after a period of storage in extreme environment condition, wait for the time necessary so that the apparatus returns to normal measuring conditions (see environments specifications paragraph 7.2).

INSTRUMENT DESCRIPTION

FRONT PANEL

LEGEND:

1. Reflecting tape.
2. Reflecting signal light beam.
3. Emitting / Receiving units.
4. UNIT key.
5. FUNCTION key.
6. START / STOP / HOLD key.
7. MAX/MIN/AVE symbols.
8. Low battery indication.
9. Start measure symbol.
10. Results display (bottom) and clock display (top) for Hours:Minutes.
11. Emitting signal light beam.

KEYS DESCRIPTION

• UNIT key
  Press ciclycally UNIT key to select the followed units:
  • RPM: speed measure without contact
  • RPM /: speed measure with contact
  • m/min: meter/minute
  • ft/min: feet/minute
  • yd/min: yards/minute
  • R/S: frequency (Hz)
  • NO.: events counter with external or internal light source

FUNCTION key

Press ciclycally FUNCTION key to select the Maximum (MAX), Minimum (MIN) and Average (AVE) values of measured parameters at display, except for events counter results. MAX, MIN and AVE are shown at display. These functions allow users to analyze the stability of rotational speed. Average value is calculated as:

If the sum of average value is overrange, or number of counting values n > 65535, the last average RPM will be used as initial value for successive calculation and n will be reset to 1.
Pressing HOLD key the MAX/MIN/AVE values are still stored in memory. Press FUNCTION key to review the values at display.
Press FUNCTION key at least 2s to return to normal mode.

START/STOP/HOLD key

• Press ON/OFF key to turn ON the meter.
• Press START key to activate any measures. “ ” symbol is shown at display.
• Press START key again to stop measures and hold the data at display. “H” symbol is shown at display.
• Press and hold ON/OFF key at least 2s to turn OFF the meter. “OFF” symbol is shown for a while.

AUTOPOWEROFF FUNCTION

• With AutoPowerOFF mode is enabled the clock meter shows Minutes only and the instruments is automatically OFF after about 30 minutes from last operation. When the meter is turn ON AutoPowerOFF is always enabled.
• To disable the AutoPOwerOFF function press and hold UNIT key at least 2s. Internal clock meter shows Hours and Minutes.

EMITTING/RECEIVING UNIT

The HT2234N meter is composed by two internal units which performing all measurements. The Emitting unit emits a light from a red LED (left side) which is reflected by reflecting tape applied on the surface of the object on test and is received by Receiving unit (right side). It is recommenced that the reflecting surface is perpendicular to the emitting/receiving unit for best measurement.

OPERATING INSTRUCTIONS

SPEED MEASURE WITHOUT CONTACT

1. Cut off a piece of reflective tape of size 1.0 cm x 1.4 cm (optimal size).
2. Wipe off oil or stains from the surface where reflective tape will be adhered.
3. Stick the self-adhesive reflective tape on the object whose rotational speed is to be measured. The reflective tape should be attached as close to the outer edge of the object to be measured as possible.
4. Press ON/OFF key to turn ON the meter.
5. Press UNIT key to select unit, RPM or R/S.
6. Aim the meter to the object on test (see Fig. 2):
7. Press START key once and confirm that the red emitting LED lamp lights up and aimed to reflective tape. symbol is shown at display.
8. Press START key again to stop the measure. “H” symbol is shown at display.
9. The result of test and his duration is shown at display.

CAUTION

• If the rotational speed is less than 60 rpm, it may take about 1 to 6 seconds to measure (60 rpm takes 1 second, and 10 rpm takes 6 seconds).
• The reading will be held for 6 seconds, if you aim the photoelectric probe at a 0 speed object right after one measurement.
• If the speed is less than 999.99 rpm, the red LED is turned on all the time to detect speed. If the speed is great than 999.99, the unit goes into powersaving mode. The LED is turned on for a very short period of time, then turned off for most of the time to save power.

SPEED MEASURE WITH CONTACT

1. Insert the proper rubber head on the mechanical adapter.
2. Attach the mechanical adaptor to the unit and fasten the screw (see Fig. 3):
3. Press ON/OFF key to turn ON the meter.
4. Press UNIT key to select RPM / unit.
5. Press against the shaft of the object to be measured. Do not press against the shaft too hard to avoid hazardus situation for operator.
6. Press START key once to enable measure. symbol is shown at display.
7. Press START key again to stop measure. “H” symbol is shown at display.
8. The result of test and his duration is shown at display.

CAUTION

• Do not exceed the speed limit of 29999 rpm when using mechanical adaptor.

SPEED MEASURES ON SURFACES (m/min, ft/min, yd/min)

1. Attach the mechanical adaptor to the unit and fasten the screw.
2. Press ON/OFF key to turn ON the meter.
3. Press UNIT key to select the desired m/min, ft/min or yd/min unit .
4. Place the mechanical adaptor in contact with the surface on test, like is shown on Fig. 4:
5. Press START key once to enable measure. symbol is shown at display.
6. Press START key again to stop measure. “H” symbol is shown at display.
7. The result of test and his duration is shown at display.

EVENTS COUNTER WITH EXTERNAL LIGHT SOURCE

1. Place the external light source strictly close to Receiving unit (right side) like is shown in Fig. 5:
2. Press ON/OFF key to turn ON the meter.
3. Press cyclically UNIT key until selecting “NO.” unit at display. On this condition the meter shows values clear for each displays. Internal clock (with Hours and Minutes) start the counter and AutoPowerOFF function is automatically disabled.
4. Press START key once to enable counter. symbol is shown at display.
5. Press START key again to stop counter. “H” symbol is shown at display.
6. The result of counters and his duration is shown at display.
7. Press FUNCTION key to reset counter.

EVENTS COUNTER WITH INTERNAL EMITTING UNIT

1. Place, if necessary, a piece of reflective tape on external surface which should be interested by red LED and place the meter like shown in Fig. 6:
2. Press ON/OFF key to turn ON the meter.
3. Press cyclically UNIT key until selecting “NO.” unit at display. On this condition the meter shows values clear for each displays. Internal clock (with Hours and Minutes) start the counter and AutoPowerOFF function is automatically disabled.
4. Press START key once to enable counter. symbol is shown at display.
5. Press START key again to stop counter. “H” symbol is shown at display.
6. The result of counters and his duration is shown at display.
7. Press FUNCTION key to reset counter.

MEASURES ON SLOW ROTATING OBJECTS

• If the rotating speed of the object on test is very slow, it is recommended that you use a tripod to hold the tachometer in place and use multiple pieces of tape for more accurate result.
• If multiple pieces of tape are used, each piece of tape should be located at the same distance to each other on the object. Any number of pieces of tape are acceptable. But you need to divide the reading by the number of pieces to obtain the correct result.

Example: 4 pieces of tape and reading is 12 rpm
Correct Speed is 12 / 4 = 3 rpm

MAINTENANCE

GENERAL INFORMATION

1. This meter is a precision instrument. Whether in use or in storage, please do not exceed the specifications to avoid any possible damage or danger during use.
2. Do not keep this meter at high temperatures and/or humidity or expose to direct sunlight.
3. Be sure to turn the meter off after use. For long term storage, remove the battery to avoid leakage of battery fluid that can damage the internal components.

BATTERIES REPLACEMENT

When battery is low, the symbol “ “is displayed to require replacement. Consider the followed steps:

1. Turn OFF the meter with ON/OFF key.
2. Open the battery cover.
3. Replace the old batteries.
4. Insert new ones of the same 1,5V AA UM-3 type.
5. Reposition the battery cover.

CLEANING

• To clean the instrument use a soft dry cloth. Never use wet clothes, solvents or water, etc.

END OF LIFE

• CAUTION: this symbol indicates that equipment and its accessories shall be subject to a separate collection and correct disposal.

TECHNICAL SPECIFICATIONS

TECHNICAL CHARACTERISTICS

Accuracy is indicated as [% of reading + number of dgts]. It is referred to the following reference conditions: 23°C ± 5°C with RH <75%.

Speed without contact

Function	Range	Resolution	Accuracy
RPM (Giri/min)	10.00 ÷ 99999	0.01 / 0.1 / 1	±(0.04% rdg +2 dgt)
RPS (Hz)	0.200 ÷ 2000.0	0.001 / 0.01 / 0.1

Speed with contact

Function	Range	Resolution	Accuracy
RPM /	20.00 ÷ 29999	0.01 /0.1 / 1	±(0.04% rdg +2 dgt)
m/min	2.000÷2999.9	0.001 / 0.01 / 0.1
ft/min	6.00 ÷ 10000	0.01 / 0.1 / 1
yd/min	4.00 ÷ 3000	0.01 / 0.1 / 1

Events Counter

Range	Maximum input frequency
0÷99999	10KHz. with 5% duty cycle

GENERAL CHARACTERISTICS

• Display: 5 digits 99999 counts
• Sampling Rate: 0.7 second (> 60 rpm)
  • > 1 second (10 to 60 rpm)
• Measuring Distance: 50 to 300 mm
• Time Base: 4.0 MHz Quartz Crystal
• Range Selection: Automatic
• Battery: 4 x 1.5V batteries (type AA, UM-3)
• AutoPowerOFF: 30 minutes
• Operating temperature: 0 ÷ 50°C (32 to 122°F)
• Dimensions: (172 x 63 x 36) mm
• Weight: 190g (included batteries)

ACCESSORIES

• HT2234N meter
• Mechanical adapter
• Fixed screw for mechanical adapter
• Reflective tape
• Rubber O-ring
• Rubber leads for measures
• Batteries
• Carrying case
• Instruction manual

SERVICE

WARRANTY CONDITION

This instrument is guaranteed against material or production defects, in accordance with our general sales conditions. During the warranty period the manufacturer reserves the right to decide either to repair or replace the product.
Should you need for any reason to return back the instrument for repair or replacement take prior agreements with the local distributor from whom you bought it.
Do not forget to enclose a report describing the reasons for returning (detected fault). Use only original packaging.

Any damage occurred in transit due to non original packaging will be charged anyhow to the customer.
The manufacturer will not be responsible for any damage to persons or things.

The warranty doesn’t apply to:

• Accessories and batteries (not covered by warranty).
• Repairs made necessary by improper use (including adaptation to particular applications not foreseen in the instructions manual) or improper combination with incompatible accessories or equipment.
• Repairs made necessary by improper shipping material causing damages in transit.
• Repairs made necessary by previous attempts for repair carried out by non skilled or unauthorized personnel.
• Instruments for whatever reason modified by the customer himself without explicit authorization of our Technical Dept.

The contents of this manual may not be reproduced in any form whatsoever without the manufacturer’s authorization.

Our products are patented and our logotypes registered. We reserve the right to modify specifications and prices in view of technological improvements or developments which might be necessary.

AFTER-SALE SERVICE

Shouldn’t the instrument work properly, before contacting your distributor make sure that batteries are correctly installed and working, check the test leads and replace them if necessary. Make sure that your operating procedure corresponds to the one described in this manual.

Should you need for any reason to return back the instrument for repair or replacement take prior agreements with the local distributor from whom you bought it. Do not forget to enclose a report describing the reasons for returning (detected fault). Use only original packaging. Any damage occurred in transit due to non original packaging will be charged anyhow to the customer.
The manufacturer will not be responsible for any damage to persons or things.

© Copyright HT ITALIA 2024

Documents / Resources

HT INSTRUMENTS HT2234N Optical Digital Tachometer [pdf] Instruction Manual HT2234N Optical Digital Tachometer, HT2234N, Optical Digital Tachometer, Digital Tachometer, Tachometer

References

• User Manual