Model 138

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Vishay Spectrol

Revision: 29-Nov-17

2

Document Number: 57033

For technical questions, contact: sferprecisionpot@vishay.com

THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT

ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000

POWER RATING CHART

PART NUMBER DESCRIPTION (for information only)

138-

2-

1-

502

xxxx

MODEL

MECHANICAL

OPTIONS

FEATURES

OHMIC VALUE

SPECIAL

DIMENSIONS in inches (millimeters)

MECHANICAL SPECIFICATIONS

PARAMETER

Rotation

360° (continuous) 340° ± 5° stops

Bearing Type

Sleeve

Torque (maximums)

STARTING

1.0 oz. - in (72 g - cm)

RUNNING

0.7 oz. - in (50.40 g - cm)

Runouts (maximums)

Shaft Runout (TIR)

0.002" (0.05 mm)

Pilot Dia. Runout (TIR)

0.003" (0.08 mm)

Lateral Runout (TIR)

0.005" (0.13 mm)

Shaft End Play

0.008" (0.20 mm)

Shaft Radial Play

0.003" (0.08 mm)

Weight

1.0 oz. maximum (28.35 g)

Stop Strength

8.0 in - lbs (9.21 kg - cm) (stops version only)

± 0.031

0.875

(22.22)

Ø 0.4062 MTG. (10.32)

+ 0.0000

- 0.0020

0.032

(0.81)

Ø 0.2497 (6.34)

0.030 MAX. (0.76)

+ 0.0000

- 0.0003

0.562 (14.27)

0.032

(0.81)

3/

8 - 32 UNEF - 2A

Ø 0.125 (3.18)

0.062 (1.57)

MTG. SURFACE

0.062

(1.57)

0.625

(15.88)

± 0.015

0.187

(4.75)

± 0.015

60°

± 0.015

Ø 0.500

(12.70)

BC

0.375

(9.52)

± 0.015

± 0.010

TOLERANCES: UNLESS OTHERWISE NOTED.

DECIMALS ± 0.005 ANGLES ± 2°

CW

SCHEMATIC

2

3

1

Ø 1.312

(33.32)

± 0.015

MODEL 138B/138-...

0

20

40

60

80

100

120

140

AMBIENT TEMPERATURE IN °C

6.0

5.0

4.0

3.0

2.0

1.0

MARKING

Unit



Identification

Units shall be marked with Vishay Spectrol

name, model number, resistance and

tolerance, linearity, terminal identification, and

data code Applicable test procedures:

MIL-R-39023



Example of a marking for a standard part:

138-2-0-502