Features
■ Multiturn / Wirewound / Sealed
■ Listed on the QPL for style RT22 per
MIL-R-27208 and RTR22 per
High-Rel MIL-R-39015
■ Panel Mount option available
(see page 73 for details)
3250/RT22/RTR22 - 1/2” Square Trimming Potentiometer
3250P/RT22/RTR22 Common Dimensions
(Pin Styles)
Electrical Characteristics
Standard Resistance Range
RED
WIPER
2
1.98
(.078)
DIA. THRU
(2 PLACES)
3250 .....................................10 to 50K ohms
RT22 .....................................50 to 20K ohms
RTR22 ................................500 to 20K ohms
(see standard resistance table)
Resistance Tolerance ........................±5% std.
(tighter tolerance available)
GREEN
CW
YELLOW
CCW
3
1
CLOCKWISE
ADJ. SLOT
2.03 ± .38
(.080 ± .015)
DIA.
13.21
TYP.
(.520)
.64
(.024)
How To Order
WIDE
X
X
Absolute Minimum Resistance
12.7
TYP.
3250 L - 1 - 103 M
3.1
.......0.1% or 1 ohm max. (whichever is greater)
Noise...............................100 ohms ENR max.
Resolution .....................See Resistance Table
Insulation Resistance .........................500 vdc.
1,000 megohms min.
DEEP
(.122)
(.500)
.89
Model
Style
(.035)
TYP.
2.54
(.100)
2.54
(.100)
6.35
Standard or Modified
Product Indicator
1.78
(.070)
TYP.
Dielectric Strength
5.59
-1 = Standard Product
.71 ± .08
Sea Level........................................1,000 vac
80,000 Feet .......................................400 vac
Adjustment Travel......................25 turns nom.
(.220)
DIA. TYP.
(.028 ± .003)
Resistance Code
(.250)
3
Optional Suffix Letter
12.7
(.500)
TYP.
M = Panel Mount
2
Environmental Characteristics
Power Rating @ 85°C
(Factory Installed)
1
3250 ..................................................1.0 watt
RT22/RTR22 ...................................0.75 watt
Power Rating @ 150°C ..........................0 watt
Temperature Range...............-65°C to +150°C
Temperature Coefficient
3250 ............................................±50ppm/°C
RT22/RTR22................................±50ppm/°C
Seal Test .......85°C Fluorinert* (pin styles only)
Humidity ................MIL-STD-202 Method 106
3250 ..................(2% ∆TR; 100 Megohms IR)
RT22....................(1% ∆TR; 10 Megohms IR)
RTR22 ...............(1% ∆TR; 100 Megohms IR)
Vibration ....................................................30G
(1% ∆TR; 0.5% + resolution ∆VR)
Shock ......................................................100G
(1% ∆TR; 0.5% + resolution ∆VR)
Load Life
3250 ................1,000 hours 1.0 watt @ 85°C
(2% ∆TR; 500 ohms ENR)
RT22 .............1,000 hours 0.75 watt @ 85°C
(2% ∆TR; 2% + resolution ∆VR)
2.54
(.100)
See page 80 for RT22/RTR22 ordering
information.
13.33 ± .64
(.525 ± .025)
6.35
(.250)
Consult factory for other available options.
3250W/RT22/RTR22
2.79
(.110)
3
2
1
Standard Resistance Table
6.35
(.250)
Nominal
Resistance
Code
2.54
(.100)
2.54
(.100)
Resistance
(Ohms)
Resolution
(Percent)
10
20
50
100
200
500
1.30
1.00
0.80
3250W-66/RT22X/RTR22X
2.79
(.110)
3
2
100
200
101
201
501
102
202
502
103
203
0.90
0.70
0.60
0.40
0.30
0.25
0.19
0.16
1
500
1,000
2,000
5,000
10,000
20,000
6.35
(.250)
2.54
(.100)
2.54
(.100)
RTR22 .........10,000 hours 0.75 watt @ 85°C
(3% ∆TR; 2% + resolution ∆TR)
Rotational Life.................................200 cycles
3250 .....................(2% ∆TR; 500 ohms ENR)
RT22/RTR22 ...................................(2% ∆TR)
"L" Flex Lead Type
RT22 has mounting slots
RTR22 has mounting holes
25,000
50,000
253
503
0.14
0.13
13.21
(.520)
TYP.
Popular values listed in boldface. Special
resistances available.
Physical Characteristics
2.36
(.093)
DIA. THRU
(2 PLACES)
SHADED AREAS TYPICALLY NOT STOCKED BY
DISTRIBUTORS AND NOT RECOMMENDED FOR NEW
DESIGNS.
Torque ......................................5.0 oz-in. max.
Mechanical Stops ..........................Wiper idles
Terminals
3250..............Solderable printed circuit pins
Flexible leads (7 strands of 30 AWG)
RT22/RTR22 .......MIL-STD-202; Method 208
Weight .................................................0.06 oz.
Machine Screw Mounting
Torque .....................................12 oz-in. max.
Marking
3250.....................Manufacturer’s trademark,
resistance code, terminal numbers,
date code, manufacturer’s model
.89
(.035)
TYP.
12.70
TYP.
(.500)
1.40
(.055)
152.4
(6.00)
LENGTH
MIN.
4.75
(.187)
1.52
(.060)
12.7
(.500)
TYP.
number and style
RT22/RTR22 ..............Mil-spec part number
Wiper ........................................Set at CW end
Flammability....................................U.L. 94V-0
Standard Packaging
P&W Styles ..........................25 pcs. per tube
L Style...................................25 pcs. per bag
Adjustment Tool.......................................H-90
TOLERANCES: ± 0.25 (.010) EXCEPT WHERE NOTED
METRIC
DIMENSIONS ARE:
(INCHES)
*”FLUORINERT” IS A REGISTERED TRADEMARK OF 3M CO.
Specifications are subject to change without notice.
16
BOURNS [ BOURNS ELECTRONIC SOLUTIONS ]
