Contact Us:00852-30501886 Email:sales@allicdata.com
Sitemap How to buy Login / Register
USD
USA EN
Cart(0)
Products Manufacturers Authorized Agent Send RFQ Blog（news） About us
Home> Products>

Search Result:red resistor

 --115 Item(s) In Category:Box Components

Related Categories

Resistors
Through Hole Resistors
Resistor Networks, Arrays
Chassis Mount Resistors
Specialized Resistors
Accessories
Chip Resistor - Surface Mount
Switches
Pushbutton Switches
Rocker Switches
Toggle Switches
Accessories - Caps
Selector Switches
Configurable Switch Components...
Tactile Switches
Accessories
Optoelectronics
LED Indication - Discrete
Panel Indicators, Pilot Lights
LEDs - Circuit Board Indicator...
Display Modules - LED Characte...
Display Modules - LCD, OLED, G...
LED Lighting - Color
Display Modules - LED Dot Matr...
LED Lighting - COBs, Engines, ...
LEDs - Lamp Replacements
Optics - Lenses
Addressable, Specialty
Display Modules - LCD, OLED Ch...
Accessories
Optics - Light Pipes
Sensors, Transducers
Optical Sensors - Photoelectri...
Encoders
Optical Sensors - Photointerru...
Accessories
Discrete Semiconductor Products
Transistors - Bipolar (BJT) - ...
Transistors - Bipolar (BJT) - ...
Cable Assemblies
Jumper Wires, Pre-Crimped Lead...
Modular Cables
Fiber Optic Cables
LGH Cables
Circular Cable Assemblies
Between Series Adapter Cables
Connectors, Interconnects
Modular Connectors - Jacks
Rectangular Connectors - Free ...
Terminals - Ring Connectors
Terminals - Quick Connects, Qu...
Terminals - Spade Connectors
Rectangular Connectors - Heade...
Power Entry Connectors - Inlet...
Rectangular Connectors - Housi...
Terminals - Wire Splice Connec...
Terminals - Rectangular Connec...
Banana and Tip Connectors - Ja...
Rectangular Connectors - Heade...
Terminal Blocks - Accessories ...
Terminal Junction Systems
Terminal Blocks - Din Rail, Ch...
Terminal Blocks - Accessories ...
Circular Connectors - Accessor...
Barrel - Audio Connectors
Terminals - Specialized Connec...
Keystone - Inserts
Cables, Wires
Single Conductor Cables (Hook-...
Flat Ribbon Cables
Multiple Conductor Cables
Uncategorized
Miscellaneous
Hardware, Fasteners, Accessories
Labels, Labeling
Tapes, Adhesives, Materials
Tape
Test and Measurement
Test Leads - Banana, Meter Int...
Test Leads - BNC Interface
Test Leads - Jumper, Specialty
Test Clips - Alligator, Crocod...
Accessories
Test Clips - Grabbers, Hooks
Test Probe Tips
Test Leads - Oscilloscope Prob...
Cables, Wires - Management
Heat Shrink Tubing
Protective Hoses, Solid Tubing...
Cable Ties and Cable Lacing
Labels, Labeling
Markers
Networking Solutions
Switches, Hubs
Miscellaneous
Potentiometers, Variable Resisto...
Adjustable Power Resistor
Trimmer Potentiometers
Industrial Controls
Panel Meters
Panel Meters - Accessories
Panel Meters - Counters, Hour ...
Controllers - Process, Tempera...
Accessories
Machine Vision - Lighting
Circuit Protection
Circuit Breakers
Disconnect Switch Components
Fuses
Kits
Resistor Kits
Fans, Thermal Management
Thermal - Pads, Sheets
Relays
Automotive Relays
I/O Relay Modules
Boxes, Enclosures, Racks
Boxes
Box Components
Tools
Heat Guns, Torches, Accessorie...
Motors, Solenoids, Driver Boards...
Accessories
Photo Allicdata Part# Mft.Part# Company Spec. QTY. Pricing(USD) PDF
DMB-4778-IRC 377-2673-ND DMB-4778-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 RoHS Status: RoHS Compliant
 Type: Cover Plate
 For Use With/Related Products: DMB-4778
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
25
Order

1+:

$1.449

5+:

$1.323

10+:

$1.197

25+:

$1.071

50+:

$1.008

100+:

$0.945

250+:

$0.882

500+:

$0.8663

1000+:

$0.8505

 377-2673-ND Datasheet
DMB-4775-IRC 377-2669-ND DMB-4775-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 RoHS Status: RoHS Compliant
 Type: Cover Plate
 For Use With/Related Products: DMB-4775
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
25
Order

1+:

$1.1088

5+:

$1.0244

10+:

$0.9419

25+:

$0.7575

50+:

$0.6962

100+:

$0.6552

250+:

$0.6143

500+:

$0.5733

1000+:

$0.5631

 377-2669-ND Datasheet
1455JALRD-10 1455JALRD-10-ND 1455JALRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 RoHS Status: RoHS Compliant
 Type: Panel, End
 For Use With/Related Products: 1455J Series
 Color: Red
 Material: Aluminum
1000
Order

1+:

$0

 1455JALRD-10-ND Datasheet
DMB-4769-IRC 377-2641-ND DMB-4769-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMB-4769
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
34
Order

1+:

$0.567

6+:

$0.4725

100+:

$0.441

200+:

$0.378

 377-2641-ND Datasheet
2956893 2956893-ND 2956893 Phoenix Contact
View more  Series: UM
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Panel, Side
 For Use With/Related Products: UM Series
 Color: Red
 Material: Plastic, Non Specified
1000
Order

10+:

$3.3138

 2956893-ND Datasheet
4008R 4008R-ND 4008R Serpac
View more  Series: M
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Lens
 For Use With/Related Products: M6, M8 Series
 Size / Dimension: 2.200" L x 0.440" W x 0.070" H (55.88mm x 11.18mm x 1.78mm)
 Color: Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$1.9152

 4008R-ND Datasheet
DMB-4770-IRC DMB-4770-IRC-ND DMB-4770-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMB-4770
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
1000
Order

1+:

$0.378

 DMB-4770-IRC-ND Datasheet
96310200 902-1252-ND 96310200 Bopla Enclosures
View more  Series: Bocube
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Panel, End
 Features: Hinged, Lock
 For Use With/Related Products: 130mm Width Boxes
 Color: Red
 Material: Plastic, Polycarbonate
8
Order

1+:

$2.2491

5+:

$2.0513

 902-1252-ND Datasheet
DMB-4772-IRC DMB-4772-IRC-ND DMB-4772-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMB-4772
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
1000
Order

1+:

$0.756

 DMB-4772-IRC-ND Datasheet
DMB-4771-IRC DMB-4771-IRC-ND DMB-4771-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMB-4771
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
1000
Order

1+:

$0.693

 DMB-4771-IRC-ND Datasheet
96310100 902-1248-ND 96310100 Bopla Enclosures
View more  Series: Bocube
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Panel, End
 Features: Hinged, Lock
 For Use With/Related Products: 80mm Width Boxes
 Color: Red
 Material: Plastic, Polycarbonate
1000
Order

10+:

$1.4125

 902-1248-ND Datasheet
DMB-4773-IRC DMB-4773-IRC-ND DMB-4773-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMB-4773
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
1000
Order

1+:

$0.945

 DMB-4773-IRC-ND Datasheet
96310300 902-1256-ND 96310300 Bopla Enclosures
View more  Series: Bocube
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Panel, End
 Features: Hinged, Lock
 For Use With/Related Products: 170mm Width Boxes
 Color: Red
 Material: Plastic, Polycarbonate
1000
Order

10+:

$2.7525

 902-1256-ND Datasheet
DMB-4774-IRC DMB-4774-IRC-ND DMB-4774-IRC Bud Industries
View more  Series: DMB
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMB-4774
 Color: Infra-Red
 Material: Plastic, ABS/PC Blend
1000
Order

1+:

$1.071

 DMB-4774-IRC-ND Datasheet
1455LBTRD 1455LBTRD-ND 1455LBTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455L Series
 Size / Dimension: 4.178" L x 1.324" W x 0.354" H (106.12mm x 33.63mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$6.678

 1455LBTRD-ND Datasheet
DMX-4785-IR 377-2182-ND DMX-4785-IR Bud Industries
View more  Series: DMX
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Cover, Lid
 For Use With/Related Products: DMX Series
 Size / Dimension: 3.871" L x 2.717" W x 0.276" H (98.33mm x 69.01mm x 7.00mm)
 Color: Infra-Red
 Material: Plastic, Polycarbonate
15
Order

1+:

$1.134

 377-2182-ND Datasheet
1455JBTRD 1455JBTRD-ND 1455JBTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455J Series
 Size / Dimension: 3.194" L x 1.186" W x 0.354" H (81.13mm x 30.12mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$6.678

 1455JBTRD-ND Datasheet
1455NBTRD-10 1455NBTRD-10-ND 1455NBTRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455N Series
 Size / Dimension: 4.178" L x 2.210" W x 0.354" H (106.12mm x 56.13mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$23.4738

 1455NBTRD-10-ND Datasheet
2015,IR SRA31-IR-ND 2015,IR Serpac
View more  Series: A
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Panel, End
 For Use With/Related Products: A31 Series
 Size / Dimension: 4.910" L x 1.520" W x 0.100" H (124.71mm x 38.61mm x 2.54mm)
 Color: Infra-Red
 Material: Plastic, Polycarbonate
1000
Order

25+:

$1.4674

 SRA31-IR-ND Datasheet
1455LBRED 1455LBRED-ND 1455LBRED Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455L Series
 Size / Dimension: 4.178" L x 1.324" W x 0.354" H (106.12mm x 33.63mm x 8.99mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$3.78

 1455LBRED-ND Datasheet
1455KPLTRD-10 1455KPLTRD-10-N
D		 1455KPLTRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455K Series
 Size / Dimension: 3.194" L x 1.816" W x 0.354" H (81.13mm x 46.13mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$23.4738

 1455KPLTRD-10-ND Datasheet
2003,IR SRA20-IR-ND 2003,IR Serpac
View more  Series: A
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Panel, End
 For Use With/Related Products: A20 Series
 Size / Dimension: 2.486" L x 0.745" W x 0.060" H (63.14mm x 18.92mm x 1.52mm)
 Color: Infra-Red
 Material: Plastic, Polycarbonate
4
Order

1+:

$1.3293

5+:

$1.2285

10+:

$1.1302

25+:

$0.9092

50+:

$0.8354

100+:

$0.7862

250+:

$0.7371

500+:

$0.688

1000+:

$0.6757

 SRA20-IR-ND Datasheet
1455TBTRD 1455TBTRD-ND 1455TBTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455T Series
 Size / Dimension: 6.673" L x 2.190" W x 0.453" H (169.49mm x 55.63mm x 11.51mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.7805

 1455TBTRD-ND Datasheet
1455TPLTRD 1455TPLTRD-ND 1455TPLTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455T Series
 Size / Dimension: 6.673" L x 2.190" W x 0.453" H (169.49mm x 55.63mm x 11.51mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.4025

 1455TPLTRD-ND Datasheet
1455RBRED-10 1455RBRED-10-ND 1455RBRED-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455R Series
 Size / Dimension: 6.673" L x 1.363" W x 0.453" H (169.49mm x 34.62mm x 11.51mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$13.5198

 1455RBRED-10-ND Datasheet
1455PBTRD 1455PBTRD-ND 1455PBTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455P Series
 Size / Dimension: 5.079" L x 1.344" W x 0.413" H (129.01mm x 34.14mm x 10.49mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.2261

 1455PBTRD-ND Datasheet
1455PPLRED-10 1455PPLRED-10-N
D		 1455PPLRED-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455P Series
 Size / Dimension: 5.079" L x 1.344" W x 0.413" H (129.01mm x 34.14mm x 10.49mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$25.2756

 1455PPLRED-10-ND Datasheet
1455NBTRD 1455NBTRD-ND 1455NBTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455N Series
 Size / Dimension: 4.178" L x 2.210" W x 0.354" H (106.12mm x 56.13mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.2261

 1455NBTRD-ND Datasheet
1455LPLTRD 1455LPLTRD-ND 1455LPLTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455L Series
 Size / Dimension: 4.178" L x 1.324" W x 0.354" H (106.12mm x 33.63mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.2261

 1455LPLTRD-ND Datasheet
1455NPLTRD 1455NPLTRD-ND 1455NPLTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455N Series
 Size / Dimension: 4.178" L x 2.210" W x 0.354" H (106.12mm x 56.13mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.7805

 1455NPLTRD-ND Datasheet
1455RPLRED 1455RPLRED-ND 1455RPLRED Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455R Series
 Size / Dimension: 6.673" L x 1.363" W x 0.453" H (169.49mm x 34.62mm x 11.51mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$4.221

 1455RPLRED-ND Datasheet
1455RPLTRD 1455RPLTRD-ND 1455RPLTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455R Series
 Size / Dimension: 6.673" L x 1.363" W x 0.453" H (169.49mm x 34.62mm x 11.51mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$7.4025

 1455RPLTRD-ND Datasheet
1455LPLRED 1455LPLRED-ND 1455LPLRED Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455L Series
 Size / Dimension: 4.178" L x 1.324" W x 0.354" H (106.12mm x 33.63mm x 8.99mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$4.0257

 1455LPLRED-ND Datasheet
1455LPLTRD-10 1455LPLTRD-10-N
D		 1455LPLTRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455L Series
 Size / Dimension: 4.178" L x 1.324" W x 0.354" H (106.12mm x 33.63mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$23.4738

 1455LPLTRD-10-ND Datasheet
1455PBTRD-10 1455PBTRD-10-ND 1455PBTRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455P Series
 Size / Dimension: 5.079" L x 1.344" W x 0.413" H (129.01mm x 34.14mm x 10.49mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$23.4738

 1455PBTRD-10-ND Datasheet
1455CBTRD 1455CBTRD-ND 1455CBTRD Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455C Series
 Size / Dimension: 2.131" L x 1.029" W x 0.354" H (54.13mm x 26.14mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$6.678

 1455CBTRD-ND Datasheet
1455TPLRED-10 1455TPLRED-10-N
D		 1455TPLRED-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455T Series
 Size / Dimension: 6.673" L x 2.190" W x 0.453" H (169.49mm x 55.63mm x 11.51mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$14.5089

 1455TPLRED-10-ND Datasheet
1455LBTRD-10 1455LBTRD-10-ND 1455LBTRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455L Series
 Size / Dimension: 4.178" L x 1.324" W x 0.354" H (106.12mm x 33.63mm x 8.99mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$21.6594

 1455LBTRD-10-ND Datasheet
1455TPLTRD-10 1455TPLTRD-10-N
D		 1455TPLTRD-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455T Series
 Size / Dimension: 6.673" L x 2.190" W x 0.453" H (169.49mm x 55.63mm x 11.51mm)
 Color: Translucent - Red
 Material: Plastic, Polycarbonate
1000
Order

1+:

$27.0774

 1455TPLTRD-10-ND Datasheet
1455PBRED-10 1455PBRED-10-ND 1455PBRED-10 Hammond Manufacturing
View more  Series: 1455
 Part Status: Active
 Lead Free Status / RoHS Status: Lead free / RoHS Compliant
 Type: Bezel
 For Use With/Related Products: 1455P Series
 Size / Dimension: 5.079" L x 1.344" W x 0.413" H (129.01mm x 34.14mm x 10.49mm)
 Color: Red
 Material: Plastic, ABS
1000
Order

1+:

$12.6315

 1455PBRED-10-ND Datasheet
Hot Searches: red red brown resistor red resistor voltage red led resistor brown black red resistor red led resistor resistor voltage resistor resistor voltage constant resistor metal resistor resistor divider resistor calculator variable resistor 1k resistor 10k resistor ballast resistor resistor values shunt resistor resistor in parallel load resistor