Wavetek CT-235, CT-237 User Manual [en, de, fr]

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TM

Operator’s Manual

CT-235, CT-237

AC/DC Current Probes

•Bedienungsanleitung

•Manuel d’Utilisation

Accessory

WARRANTY

The CT235 and CT237 Current Clamps are warranted against any defects of material or workmanship within a period of one (1) year following the date of purchase of the multimeter by the original purchaser or original user. Any multimeter claimed to be defective during the warranty period should be returned with proof of purchase to an authorized Wavetek Meterman Service Center or to the local Wavetek Meterman dealer or distributor where your multimeter was purchased. See maintenance section for details. Any implied warranties arising out of the sale of a Wavetek Meterman multimeter, including but not limited to implied warranties of merchantability and fitness for a particular purpose, are limited in duration to the above stated one (1) year period. Wavetek Meterman shall not be liable for loss of use of the multimeter or other incidental or consequential damages, expenses, or economical loss or for any claim or claims for such damage, expenses or economical loss.

Some states do not allow limitations on how long implied warranties last or the exclusion or limitation of incidental or consequential damages, so the above limitations or exclusions may not apply to you.

This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.

WARNINGS AND PRECAUTION

PLEASE READ SECTION 2 – SPECIFICATION BEFORE OPERATING THE INSTRUMENT

Exceeding the maximum limits of this instrument is DANGEROUS.

Exceeding these limits will expose you to physical injury or even death and will almost certainly damage your instrument. Even low-level voltages and currents are capable of causing serious injury or even death.

Please do not use this or any piece ot test equipment without proper training. Individual functions and ranges have different overload limits. It is VERY IMPORTANT that you make yourself aware of these overload limits. Check the specifications of these overload limits.

OPERATING INSTRUCTIONS

International Electrical Symbols

Caution! Refer to this manual before using the probe.

Probe is protected by Reinforced or Double Insulation.

CONTENTS

	Warranty Statement	Page 1
1	INTRODUCTION	Page 1
2	SPECIFICATIONS
2.1	Electrical Data	Page 2
2.2	General Data	Page 2
3	OPERATING INSTRUCTIONS
3.1	Switch On	Page 3
3.2	Zero Adjustment	Page 3
3.3	Current Measurement	Page 3
4	SAFETY	Page 3
5	BATTERY REPLACEMENT	Page 3
6	FACTORY SERVICE	Page 4
7	FREQUENCY RESPONSE
	AND ACCURACY CURVES	Page 7

1. INTRODUCTION

The CT-235 and the CT-237 current probes have been designed for use with digital multimeters, recorders and other suitable equipment for accurate nonintrusive measurement of AC, DC and complex waveform currents.

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Using advanced Hall Effect technology the CT-237 can accurately measure currents up to 200 A r.m.s. over the frequency range of DC to 10 kHz, while the CT-235 measures currents up to 1000A DC or AC peak. These features make them powerful tools for use in inverters, switch mode power supplies, industrial controllers, automotive diagnostics and other applications requiring accurate isolated current measurement.

2. SPECIFICATIONS

2.1 Electrical data

(All accuracies stated at 23°C ± 1°C)

Current ranges
CT-237	20A and 200A DC and AC r.m.s.
CT-235	200A and 1000A DC and AC peak
Overload capacity	1000 %
Overall accuracy
CT-237, 20A range DC	±1% of rdg ± 0.03A
20A range AC, <5kHz	±1% of rdg ± 0.03A
5kHz to 10kHz	±2% of rdg ± 0.03A
CT-237, 200A range DC	±1% of rdg ± 0.3A
200A range AC, <2kHz	±1% of rdg ± 0.3A
2kHz to 5kHz:	±2% of rdg ±0,3A
5kHz to 10kHz:	±5% of rdg ±0,3A
CT-235, 200A/1000A range, DC±1% of rdg ± 0.5A
200A/1000A range, AC, <10kHz ±1% of rdg ± 0.5A
Resolution
CT-237, 20A range	± 10mA
CT-237, 200A range	± 100mA
CT-235, 200A range	± 100mA
CT-235, 1000A range	± 100mA
Temperature coefficient	± 0.1% of reading/°C
Output sensitivity
CT-237, 20A range	10 mV/A
CT-237, 200A range	1mV/A
CT-235, 200A range	1 mV/A
CT-235, 1000A range	1 mV/A
Frequency range ( -1dB)	DC to 10 kHz (limited by eddy
current heating for Irms x f >400,000)
Dielectric strength	3.7kV r.m.s. 50 Hz for 1 min

Safety: Meets EN61010-1 Cat III 300V; EN61010-2-032 EMC: Meets EN50081-1, EN50082-1

EMC: This product complies with requirements of the following European Community Directives: 9/336/EEC (Electromagnetic

Compatibility) and 73/23/EEC (Low Voltage) as amended by 93/68/EEC (CE Marking).

2.2 General data
Operating temperature	0°C to +50°C
Storage temperature with
battery removed	- 20°C to +85°C
Power supply	9 V, Alkaline battery
PP3, NEDA 1604 or IEC6F22
Battery life	50 hours typical
Load impedance (minimum) >10 kΩ and ≤ 100pF
Conductor size
CT-237	19 mm
CT-235	31 mm
Jaw opening
CT-237	20 mm max.
CT-235	32 mm max.
Weight
CT-237	250 g.
CT-235	295 g.

Output cable and connectors 1.5 m long terminated with 4mm safety plugs

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3. OPERATING INSTRUCTIONS

Refer to Fig. 1 for the CT-237 and Fig. 2 for the CT-235 (pages 5 & 6).

3.1 Switch On

When the probe is switched on the red LED will illuminate. If the LED starts flashing this warns the user that the battery voltage is too low for normal operation and that it should be changed as described in section 5.

3.2 Zero Adjustment

The output zero offset voltage of the probe may change due to thermal shifts and other environmental conditions. To adjust the output voltage to zero depress the thumbwheel and rotate. Ensure that the probe is away from the current carrying conductor whilst the adjustment is made.

3.3 Current Measurement

Switch on the probe using the On - Off switch and check that the LED is lit. Select the required current range ( 20 Amp or 200 Amp for the CT-237; 200A or 1000A for the CT-235).

Connect the output lead to a multimeter. Select AC millivolts to measure Alternating Current and DC millivolts for Direct Current. Autoranging meters will automatically select the correct range.

If necessary adjust the probe output voltage to zero as described in section 3.2. Clamp the jaws of the probe round the conductor ensuring a good contact between the closing faces of the jaws.

Observe and take measurements as required. Positive output indicates that the current flow is in the direction shown by the arrow on the probe.

True r.m.s. readings can be obtained by using an appropriate true r.m.s. reading multimeter.

Core eddy current heating is produced when Irms x f >400,000.

4. SAFETY

This instrument is designed to be safe under the following conditions:

-indoor use

-altitude up to 2000m

-temperature 0°C to +50°C

-maximum relative humidity 80% for temperatures up to 31°C decreasing linearly to 40% relative humidity at 50°C.

Use of the probe on uninsulated conductors is limited to 300V r.m.s or d.c. and frequencies below 1kHz.

Safety in its use is the responsibility of the operator who must be a suitably qualified or authorised person.

Do not use the probe if any part of the probe including the lead and connector(s) appear to be damaged or if a malfunction of the instrument is suspected. When using the probe ensure that your fingers are behind the protective barrier see Fig. 1

Clean the case periodically by wiping it with a damp cloth and detergent. Do not use abrasive cleaners or solvents. Do not immerse the probe in liquids.

5. BATTERY REPLACEMENT

SAFETY WARNING: Before removing the battery cover, make sure that the probe is remote from any live electrical circuit.

The red LED will flash when the minimum operating voltage is approached. Refer to Fig.1. and use the following procedure.

Unclamp the probe from the conductor, turn it off using the On - Off switch and disconnect the output leads from external equipment. Loosen the captive screw which secures the battery cover. Lift the cover through 30° and pull it clear of the probe body as shown in Fig 1. The battery is then accessible. Replace the battery and re-fit the battery cover and fasten the screw.

Replacement with other than the specified type of battery will invalidate the warranty. Fit only Type 9 V PP3, Alkaline (MN 1604 ).

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BATTERY COVER SCREW (CAPTIVE)

SCHRAUBE, BATTERIEFACH

VIS, COMPARTIMENT PILE

JAWS

ZANGE

BATTERY COVER PINCE

BATTERIEFACHDECKEL

COUVERCLE, COMP.

PILE

	ZERO ADJUST
	NULLABGLEICH	PROTECTIVE BARRIER
	AJUSTAGE DU
		SCHUTZSPERRE
	ZERO
		BOUCLIER DE
		PROTECTION
		ZERO
		ADJUST
		OFF 20A 200A

ON CT237	ON/OFF SWITCH
AC/DC CURRENT PROBE
MAX CURRENT: 200A RMS	EIN/AUS SCHALTER
OUTPUT: 10mV/A 1mV/A

LED	BOUTON MARCHE/
	ARRET

Fig. 1

6. SERVICE INFORMATION

Read the warranty located at the front of this manual before requesting warranty or non-warranty repairs. For warranty repairs, any multimeter claimed to be defective can be returned to any Wavetek Meterman authorized distributor or to a Wavetek Meterman Service Center for an over-the-counter exchange for the same or like product. Non-warranty repairs should be sent to a Wavetek Meterman Service Center. Please call Wavetek Meterman or enquire at your point of purchase for the nearest location and current repair rates. All multimeters returned for warranty or non-warranty repair or for calibration should be accompanied by the following information or items: company name, customer’s name, address, telephone number, proof of purchase (warranty repairs), a brief description of the problem or the service requested, and the appropriate service charge (for non-warranty repairs). Please include the test leads with the meter. Service charges should be remitted in the form of a check, a money order, credit card with expiration date, or a purchase order made payable to Wavetek Meterman or to the specific service center. For minimum turn-around time on out-of-warranty repairs please phone in advance for service charge rates. The clamp should be shipped with transportation charges prepaid to one of the following addresses or to a service center:

in U.S.A.	in Canada	in Europe
Wavetek Meterman	Wavetek Meterman	Wavetek Meterman
1420 75th Street SW	400 Britannia Rd. E.Unit #1	52 Hurricane Way
Everett, WA 98203	Mississauga, ON L4Z 1X9	Norwich, NR6 6JB, U.K.
Tel: [phone]	Tel: [phone]	Tel: int + 44-1603-404824
Fax: [phone]	Fax: [phone]	Fax: int + 44-1603-
482409

The instrument will be returned with the transportation charges paid by Wavetek Meterman.

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7. FREQUENCY RESPONSE AND ACCURACY CURVES

FrequencyFrequencyin Hz •inFrequenzHz; in Hz; Fréquence• en Hz en Hz

	10	100	1000	10000
	1
dB	0,5
endB
				200A Range
•GainGainen	0
				20A Range
VerstärkungindBindB;VerstärkungindB;	-0,5
	-1
	-1,5		Frequency Response CT-237
			Frequenzgang CT-237
	-2		Réponse de Fréquence CT-237
dB•Gain
Gain in	-2,5
	-3

Phase shift in degrees • Phasenverschiebung in Grad

Frequency in Hz • Frequenzquenzin Hz • Fréquence en Hz

Frequency in Hz; in Hz; Fréquence Hz

	10	100	1000	10000
Degrés	0
Déphasageen	-2
inGrad;			Frequenzgang CT-237
degrésPhasenverschiebung	-4
	-6		Frequency Response CT-237
DéphasageenPhaseShiftinDegrees;		Réponse de Fréquence CT-237
	-10
	-8
•

Frequency in Hz • Frequenz in Hz • Fréquence en Hz

		10	Frequency in Hz	100	Frequenz in Hz	1000	Fréquence en Hz	10000
		1
en dB	dB
• Verstärkung in dB • Gain	indB;VerstärkungindB;Gainen	0
		-1
					Frequency Response CT-235
		-2			Frequenzgang CT-235
				Réponse de Fréquence CT-235
dB	Gain
Gain in		-3

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