IET Labs W10MT3A User manual

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www.ietlabs.com
IET LABS, INC.
Email: [email protected]
♦PrEcision insTrumEnTs For TEsT And mEAsurEmEnT ♦
W10MT3A
Variac Autotransformer
Operation Manual
Copyright © 2023 IET Labs, Inc.
Visit www.ietlabs.com for manual revision updates

TEL: [phone] • [phone] • FAX: [phone]
www.ietlabs.com
IET LABS, INC.
Email: [email protected]
♦PrEcision insTrumEnTs For TEsT And mEAsurEmEnT ♦

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WARRANTY
We warrant that this product is free from defects in material and workmanship and, when properly
used, will perform in accordance with applicable IET specications. If within one year after original
shipment, it is found not to meet this standard, it will be repaired or, at the option of IET, replaced at
no charge when returned to IET. Changes in this product not approved by IET or application of volt-
ages or currents greater than those allowed by the specications shall void this warranty. IET shall
not be liable for any indirect, special, or consequential damages, even if notice has been given to the
possibility of such damages.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED,
INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY
OR FITNESS FOR ANY PARTICULAR PURPOSE.

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WARNING
OBSERVE ALL SAFETY RULES
WHEN WORKING WITH HIGH VOLTAGES OR LINE VOLTAGES.
Dangerous voltages may be present inside this instrument. Do not open the case
Refer servicing to qualied personnel
HIGH VOLTAGES MAY BE PRESENT AT THE TERMINALS OF THIS INSTRUMENT
WHENEVER HAZARDOUS VOLTAGES (> 45 V) ARE USED, TAKE ALL MEASURES TO
AVOID ACCIDENTAL CONTACT WITH ANY LIVE COMPONENTS.
USE MAXIMUM INSULATION AND MINIMIZE THE USE OF BARE
CONDUCTORS WHEN USING THIS INSTRUMENT.
Use extreme caution when working with bare conductors or bus bars.
WHEN WORKING WITH HIGH VOLTAGES, POST WARNING SIGNS AND
KEEP UNREQUIRED PERSONNEL SAFELY AWAY.
CAUTION
DO NOT APPLY ANY VOLTAGES OR CURRENTS TO THE TERMINALS OF THIS
INSTRUMENT IN EXCESS OF THE MAXIMUM LIMITS INDICATED ON
THE FRONT PANEL OR THE OPERATING GUIDE LABEL.

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W10MT3A Variac
INPUT POWER: Metered Variac Autotransformers are supplied with a three-wire cord
and plug for connection to 50-to 60-cycle nominal l20-volt power line. The third wire in
the cord-plug circuit provides automatic grounding of external metal parts, as a safety
feature. Do not attempt to operate the units on direct current, or damage will result.
LOADS: Metered Variac Autotransformers are suitable for the control of any alternating-
current load within their rating of 10 amperes Since they are connected for overvoltage
(117% of line) operation, care must be taken to avoid damage to loads that are incapable
of withstanding higher-than-line voltage. Metered models are, of course, particularly
useful in determining load current, or watts, versus applied voltage.
SWITCHING: To avoid possible destructive surges, set the control knob to the full
counter clockwise (zero voltage) position before connecting the autotransformer to
the line, or the load to the autotransformer. Slowly rotate the control knob clockwise
(increasing the voltage), and observe the meter. Unusually high readings signify trouble;
the voltage should be returned to zero and the trouble corrected. The meter range is
changed by a current transformer for highest possible accuracy; make-before-break
contacts permit switching under load.
ACCESS: No user-serviceable parts inside.
FUSE: The meter circuit of this unit are fused to prevent overload damage to the meter
movements. The fuse required is: 12 ampere Bussman Type ABC-12. These are fast-
blow types; replacement with slow blow fuses or fuses of a higher rating will endanger
the meters.
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W10MT3A Variac
Specifications
Frequency: 50-60 Hz
Input Voltage: 120 volts
No-Load Loss (60-cycle): 17 watts
Output: 0-140 volts; 10 amperes, maximum
Voltmeter Range: 0-150 volts
Ammeter Range: 0-10 amperes
Meter Accuracies: ± 3% of full scale
Switching: OFF-ON, two-pole switch disconnects assembly from line in “OFF” position
Terminals:
Line-3-wire cord and plug
Load-3-wire outlet receptacle (will accept parallel 2-wire plug)
Fusing: 12-amperes BUSS ABC-12
Angle of Rotation: 320°
Driving Torque: 15-30 ounce/inches.
Case Dimensions: Width 9-5/8, height 12-5/8, depth 6-1/4 inches
Net Weight: 12 pounds (5.5 kg)
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