AC 43.13-1A Page 179 1972 Section 3. ELECTRIC WIRE
442. GENERAL, Aircraft service imposes severe environmental conditions on electric wire. To assure satisfactory service, inspect the wire at regular intervals for abrasions, defective insulation, condition of terminal posts, and buildup of corrosion under or around swaged terminals. When replacing copper wire with aluminum wire, increase the gauge of the wire two sizes.
for the circuit may be considered satisfactory.
When utilizing the voltage drop method of checking a circuit, maintain the input voltage at a constant value. Figures 11.8 and 11.4 show formulas that may be used to determine resistance in electrical wires.
FIGURE 11.3.-Examples determining voltage drop from electric wire chart (fg. 11.7).
a. Voltage Drop in Wires. The voltage drop Volt- Enter Wire in the main power wires from the generation chart Amperes aize from Check source or the battery to the bus should not ex- ceed 2 percent of the regulated voltage, when drop 100 (feet) 20 No. 6 chart VD- (.000486) (100) (20) -.872 the generator is carrying rated current or the battery is being discharged at the 5-minute 0.5 100-200 20 No. 4 VD= (.000274) rate. The following tabulation shows the maxi- 0.5 (100) (20) -,548 mum acceptable voltage drop in the load cir- 4 100-25 20 No. 12 VD= (.00188) cuits between the bus and the utilization equip- (100) (20) -8.76 ment. 7 100~14 20 No. 14' VD- (.00299)
(100) (20) -5.98 Nominal system Allowable voltage drop Intermittent voltage continuous operation operation ' It should be noted that the No. 14 wire should not be 14 0.5 1 used if any portion of its 100-foot length is to be con- 28 1 2 fined in conduit, large bundles, or locations of high 115 4 8 ambient temperature, as the intersection of the wire 200 7 14 size and current lines fall below curve 1.
' Resistance values from figure 11.5.
b. Resistance. The resistance of the current return path through the aircraft structure is FIGURE 11.4.-Examples determining voltage drop from always considered negligible. However, this is electric wire chart (fg. 11.7).
based on the assumption that adequate bonding of the structure or a special electric current re- Volt- Wire (ft.) from chart Max. length turn path has been provided which is capable drop age size Amperes at voltage drop indicated Check of carrying the required electric current with a No. 10 20 45 VD-'(.0011) negligible voltage drop. A resistance measure- (20) (45) -.990 ment of .005 ohms from ground point of the 0.5 (45) (.5)- VD-'(.0011) generator or battery to ground terminal of any 22.5 (20) (22.5) -.495 electrical device may be considered satisfactory. Another satisfactory method of determin- 4 (45) (4)- 180 VD-'(.0011) (20) (180) -8.96 ing circuit resistance is to check the voltage drop across the circuit. If the voltage drop does 7 (45) (7)- VD-'( 0011) not exceed the limit established by the aircraft 815 (20) (815) -6.98 or product manufacturer, the resistance value ' Resistance values from figure 11.5.
Chap 11 Par 442
Page 180 AC 43.13-1A 1972 FIGURE 11.5.-Copper electric wire current carrying capacity.
Specification alize MIL-W-5086 Single wire in free air maximum amperes bandled maximum Wire in conduit or amperes Maximum resistance oh i20° 0o, feet Nominal conductor area- circular milla weight-pounds per Plaished wire 1,000 feet AN-20 11 7.5 5.6 AN-18 16 10 8.4 AN-16 22 18 10.8 AN-14 82 17 17.1 AN-12 41 28 25.0 AN-10 55 38 42.7 AN-8 78 46 69.2 AN-6 101 60 102.7 AN-4 185 80 162.5 AN-2 181 100 247.6 AN-1 211 125 AN-O 245 150 882 AN-00 288 175 482 AN-000 828 200 620 AN-0000 880 225 770 FIGURE 11.6.-Aluminum electric wire current carrying capacity.
Single wire in free Maximum resistance- Piniabed wire wire sir air maximum Nominal conductor weight-pounds per Specification MII-W-7072 amperes ares- circular mille 1,000 feet AL-6 83 50 0.641 28,280 AI-4 108 66 .427 42,120 AL-2 152 90 .268 67,872 AL-O 202 .169 107,464 166 AL-00 285 •188 188,168 204 AI-000 266 .109 168,872 250 AL-0000 803 ,085 214,928 808 NoTE: Aluminum wire.-From figures 11.5 and 11.6 it will be noted that the conductor resistance of aluminum wire and that of copper wire two numbers higher are similar. Accordingly, the electric wire chart, Agure
11.5 can be used when it is desired to substitute aluminum wire and the proper size can be selected by remembering to reduce the copper wire size by two numbers and by referring to figure 11.6. The use of aluminum wire sizes smaller than No. 6 is not recommended.
443. AIRCRAFT ELECTRICAL WIRE. Use aircraftquality wire. Correct wire selection is dependent upon knowledge of current requirements, operating temperatures, and environmental conditions involved in the particular installation.
a. Conductors. Copper conductors are coated to prevent oxidation and to facilitate soldering.
Tinned copper or aluminum wire is generally used in installations where operating temperatures do not exceed 221° F. (105° C.). Silvercoated copper wire is used where temperatures Par 443 do not exceed 892° F. (200° C.). Nickel-coated copper wire is used for temperatures up to 500° F. (260° C.). Nickel-coated wire is more difficult to solder than tinned or silver-coated wire, but with proper techniques, satisfactory connections can be made.
b. Insulation. Polyvinylchloride (PVC) is a common insulation. It has good insulating properties and is self-extinguishing after the flame source is removed. Normal operating temperatures are limited to 221° F. (105° C.).
Silicone rubber is rated at 892° F. (200° C.), is Chap 11
AC 43.13-1A 1972 highly flexible, and self-extinguishing except in vertical runs. TFE Fluorocarbon (polytetrafluoroethylene) is widely used as high-temperature insulation. It will not burn, but will vaporize when exposed to flame. It is resistant to most fluids. FEP Fluorocarbon (fluorinated ethylene propolene) is rated at 892° F. (200° C.) but will melt at higher temperatures.
Other properties of FEP are similar to TFE.
c. Thermal and Abrasion Resistant Materials.
Glass braid has good thermal and abrasion qualities but moisture absorption is high. Asbestos and other minerals provide high temperature and flame resistance, but are highly absorbent. Moisture absorption is reduced by use of silicone rubber, TFE, or other saturants.
Nylon is widely used in low-temperature wires for abrasion and fuid resistance. Polyimide, a new material has excellent thermal and abrasion resistant characteristics.
d. Wire Selection. When selecting wire, refer to figure 11.7a, for structural and environmental characteristics. Wire normally used for chassis wiring, in enclosed areas, or in compact wire harnesses protected by molded or braided coverings usually has low abrasion resistance.
Wire used to interconnect units, or in long, open runs in the airframe, is designed to withstand normal aircraft environment without sleeving, jacketing, or other protection. Care must be taken in making all installations because no wire insulation or jacketing will withstand continuous scuffing or abrasion.
444. INSTRUCTIONS FOR USE OF ELECTRIC WIRE CHART. The chart is based on copper conductor meeting Specification MIL-W-5086.
Curves 1, 2, and 3 are plotted to show the maximum ampere rating for the specified wire in size and under specified conditions shown.
a. In order to select the correct size of electric wire for equipment, two major requirements must be met:
(1) The size must be sufficient to prevent an excessive voltage drop while carrying the required current over the required distance.
(2) The size must be sufficient to prevent Chap 11 Page 181 overheating of the wire while carrying the required current.
b. To simplify these determinations an electric wire chart (figure 11.7) may be used. In order to use this chart properly for the selection of wire we must know:
(1) the length in feet of the actual wire "run" from the bus to the equipment;
(2) the number of amperes of current it must carry;
(3) the amount of voltage drop permitted (see tabulation, paragraph 442a); and
(4) whether the current carried will be intermittent (maximum 2 minutes) or continuous, and if continuous, whether it is a single wire in free air, in a conduit, or in a bundle.
c. Assume that we wish to install a 50-foot length of wire from the bus to the equipment in a 28-volt system. By referring to the allowable voltage drop tablei (paragraph 442a), we find that we are permitted a 1-volt drop for continuous operation. Now referring to the "electrical wire chart" (figure 11.7), we find along the left side values numbered 5 to 200 showing the number of feet a wire may be run while carrying a given current, with a 1-volt loss or drop. Place a pointer on the horizontal line shown opposite the number 50.
d. Assuming that the current required by the equipment is 20 amperes, place another pointer at the top of the table on the diagonal line for the peo numbered 20 amperes. Now follow this diagonal line downward until it intersects the horizontal line number 50. From this point, drop straight downward to the bottom of the chart and we find that a wire size between a No. 8 and a No. 10 is required to prevent a greater drop than 1 volt. Since we are between these two numbers, select the larger size, No. 8. This is the smallest size which should be used to meet requirement a (1).
e. For requirement a (2) : (1) Disregard the length of the wire, the numbers along the left side of the chart, and the horizontal lines for this determination; (2) Assume that the wire is to be a single wire in free air carrying continuous current; (3) Place a pointer at the top Par 443
CIRCUIT ELECTRIC WIRE CHART
VOLTAGE 115|200 14 28 800 100 200 20 18 16 12 10 8 6 4 2 1% 20 % 4%
AMPERES 600 75150 WIRE LENGTH IN FEET PER VOLT DROP 400 700 100 20 25/6075 360 630 90 320 560 80 N 280 490 70 240 420 30 60 200 | 350 25 50 •*** EXAMPLE DESCRIBED IN 7 ***++*++ **** 160 280 20 40 PARAGRAPH 444 C & D CURVE 120 210 15 30 100 175 12 25 CURVE 40 CURVE 3 20 CURVES:
1. CONTINUOUS RATING - AMPERES
WIRE IN CONDUIT AND BUNDLES
2. CONTINUOUS RATING - AMPERES
SINGLE WIRE IN FREE - AIR
3. INTERMITTENT RATING - AMPERES- MAXIMUM OF 2 MINUTES 5 20 18 16 12 10* 8 4 2 1 % 20 3% 4%
WIRE SIZE Figure 11.7 FIGURE 11.7.-Dlectric wire chart.
Z261
FIGURE 11.7A--Wire used in aircraft installations.
Voltage Conductor Standard Specification Conductor Insulation rate temp. rating Bernarks MS-25190 Mil-W-5086 Tinned copper PVC, nylon 600 V. 105° C. Interconnection, low tempera- 221° F. ture gen. purpose, max. ambient temp. 60° C.
Type II Mil-W-5086 Tinned copper PVC, glass braid, nylon 600 V. 105° C. Same as Type I with greater overload protection less moisture resistance.
Tpe III Mil-77-5086 Tinned copper PVC, glass braid, PVC, 600 V. 105° C. Same as Type II. Less common.
nylon Type IV Mil-W-5086 Tinned copper PVC, nylon 3,000 V. 105° C. Similar to Type I with higher voltage rating.
MS-25191 Mil-W-7072 Aluminum PVC, glass braid, nylon 600 V. 105° C. Light weight, use 2 sizes larger braid when replacing copper. Corrosive. 60° C. ambient.
MS-25471 Mil-W-8777 Silver-coated copper Silicone rubber, glass 600 V. 200° C. High temp. interconnection.
braid, polyester braid Self-extinguishing. To 155° C. ambient.
MS-27110 Mil-W-8777 Silver-coated copper Silicone rubber, glass 600 V. 200° C. Same as MS-25417 but has braid, FEP fluoro- 392° F. smooth surface. To 155° C.
carbon ambient.
None Mil-W-7139 Silver-coated copper TFE fluorocarbon and 600 V. 200° C. High temp. interconnection.
Class 1 glass 392° F. Self-extinguishing. To 155° C.
ambient.
None Mil-W-7139 Nickel-coated copper TFE fluorocarbon and 600 V. 260° C. Same as Class 1. To 215° C.
Class 2 glass 500° F. ambient.
MS-17331 Mil-W-22759 Silver-coated copper Reinforced TFE asbestos 600 V. 200° C. Abrasion resistant, resist thermal overload.
MS-17332 Mil-W-22759 Nickel-coated copper Reinforced TFE asbestos 600 V. 260° C. Same as MS-17331.
MS-17410 Mil-W-22759 Silver-coated copper TFE, glass, FEP 600 V. 200° C. Similar to Mil-W-7139 but with smooth surface.
MS-17411 Mil-W-22759 Silver-coated copper Mineral reinforced TFE 1,000 V. 200° C. Abrasion resistant, smooth surface can be used to replace Mil-W-7139.
MS-17412 Mil-W-22759 Nickel-coated copper Mineral reinforced TFE 1,000 V. 260° C. Same as MS-17411 may be used to replace Mil-W-7139, Class
FIGURE 11.7A-Wire used in aircraft installations-continued.
Standard Specification Conduetor Insulation Voltage rate temp. rating Conductor Remarka MS-18000 Mil-W-22759 Silver-coated copper Mineral reinforced TFE 600 V. 200° C. Similar to MS-17411 and MS- 17412 with thinner wall and less abrasion resistant.
MS-18001 Mil-W-22759 Nickel-coated copper Mineral reinforced TFE 600 V. 260° C. Same as MS-1800.
MS-18032 Mil-W-22759 Silver-coated copper Fused laminated TFE 600 V. 200° C. Hook-up similar to MS-21985 and MS-21986 with thinner wall and less abrasion registance.
MS-18033 Mil-W-22759 Nickel-coated copper Fused laminated TFE 600 V. 260° C. Same as MS-18032 Laminated wall is uniform in cross section.
MS-18104 Mil-W-22759 Silver-coated copper Extruded TFE polyimide 600 V. 200° C. Similar to MS-18113 and MS- coated 18114 but thinner wall and higher abrasion resistance.
MS-18105 Mil-W-22759 Nickel-coated copper Extruded TFE polyimide 600 V. 260° C. Same as MS-18104.
coated MS-18113 Mil-W-22759 Silver-coated copper Extraded TFE 1,000 V. 200° C. Similar to MS-21985 and MS- 21986 but bigher voltage rate.
MS-18114 Mil-W-22759 Nickel-coated copper Extruded TFE 1,000 V. 260° C. Same as MS-18113.
MS-21985 Mil-W-22759 Silver-coated copper Extruded TFE 600 V. 200° C. Hook-up.
MS-21986 Mil-W-22759 Nickel-coated copper Extruded TFE 600 V. 260° C. Hook-up.
MS-27125 Mil-W-25038 Nickel-clad copper (27% Asbestos, glass, TFE 600 V. 260° C. Fire resistant. Moisture, abranickel) sion and fluid resistant where ambient temp. below 550° C.
None Mil-W-16878 Silver or nickel-coated Extraded TFE 1,000 V. 200° C. Hook-up-similar to MS-18113 Type EE copper or and MS-18114.
260° C.
M81044/1A Mil-W- Silver-plated copper Crosslinked extruded 600 V. - 65 to Aerospace electric systems 81044A polyalkene + 135 (General purpose aircraft (AS) wiring) M81044/2A Tin-coated copper normal weight M81044/3A Silver-plated copper Aerospace electric systems (General electronie wiring) 1973
M81044/4A Tin-plated copper Internal wiring of meters, panels, and electrical and electronic equipment.
M81044/5 Silver-plated copper Crosslinked extruded - 65 to Aerospace electric systems polyalkene + 150 (General purpose aircraft M81044/6 Tin-coated copper wiring) normal weight M81044/7 Silver-plated high strength copper alloy M81044/8 Silver-plated copper Aerospace electric systems (General purpose aircraft M81044/9 Tin-coated copper wiring) M81044/10 Silver-plated high medium weight strength copper alloy M81044/11 Silver-plated copper Aerospace electric systems (General electronic wiring) M81044/12 Tin-coated copper Internal wiring of meters, M81044/13 Silver-plated high panels, and electrical and elecstrength copper alloy tronic equipment.
M81381/1 Mil-W--81881 Silver-coated copper Polyimide/FEP film 600 V. -65 to Aerospace electric systems (AS) + 200 (General electronic wiring) Internal wiring of meters, M81881/2 Nickel-coated copper panels, and electrical and electronic equipment, M81381/8 Silver-coated copper Aerospace electric systems (General purpose aircraft M81881/4 Nickel-coated copper wiring) medium weight
of the table on the diagonal line which is numbered 20 amperes; (4) Follow this line until the pointer intersects the diagonal line marked "curve 2;" and (5) Drop pointer straight downward to the bottom of the chart and we are between the number 16 and 18. As the results are again between sizes, select the larger No. 16 wire. This is the smallest size wire acceptable for carrying 20-ampere current in a single wire in free air without overheating.
f. Compare the wire sizes selected. Use & cable no smaller than No. 8 in order to satisfy requirement (a) and no smaller than a No. 16 in order to satisfy requirement (b). Since we must meet both requirements, select the larger No. 8.
g. In this particular instance, the voltagedrop requirement was more critical because it required a larger size than the heat-dissipation requirement. This is usually true when a relatively light current is carried over a relatively long distance. However, when a short wire and/or a heavy current is required, the heatdissipation capabilities of the wire may become the critical factor and may dictate the size of the wire to be used.
h. The tabulation referenced in paragraph 442a shows several values of voltage drop which is allowable for various systems and conditions when selecting wire for use from the bus to the equipment. Additionally, the voltage drop permissible in wires from the generator to the bus and from the battery to the bus will vary with the regulated voltage of the system i.e., nominal 14 V., 28 V., 116 V., etc.
445. SPLICES IN ELECTRIC WIRE, Splicing of electric wire should be kept to a minimum and avoided entirelv in locations subiect to extreme AC 43.13-1A 1972 dle may be spliced provided the completed splice is located so it can be periodically inspected. Stagger splices (see figure 11.8) so the bundle does not become excessively enlarged.
Many types of aircraft splice connectors are available for use when splicing individual wires. Use of the self-insulated splice connector is preferred; however, a noninsulated splice connector may be used provided the splice is covered with plastic sleeving which is secured at both ends. Solder splices may be used; however, they are particularly brittle and not recommended.
446. OPEN WIRING. Electric wiring is often installed in aircraft without special enclosing means. This practice is known as open wiring and offers the advantages of ease of maintenance and reduced weight.
a. Wire Bundles. To simplify maintenance and to minimize the damage that may result from a single fault, limit the number of wires in the run. Shielded wire, ignition wire, and wires which are not protected by a circuit breaker or fuse usually are routed separately. Avoid bending radii less than 10 times the outer diameter of the bundle to prevent excessive stresses on the wire insulation.
b. Insulating Tubing. Soft insulating tubing (spaghetti) cannot be considered as mechanical protection against external abrasion of wire, since at best it provides only a delaying action.
Use conduit or ducting when mechanical protection is needed.
c. Clamping of Wire Bundles. Use clamps lined with nonmetallic material to support the wire bundle along the run. Tying may be used between clamps, but should not be considered as a substitute for adequate clamping. Adhe-
AC 43.13-1A Page 167 1972 therefore are not acceptable as a clamping means.
d. Separation from Flammable Fluid Lines. An arcing fault between an electric wire and a MS 21919 metallic flammable fluid line may puncture the CABLE CLAMP line and result in a serious fire. Consequently, EQUIVALENT OR make every effort to avoid this hazard by physical separation of the wire from lines or equipment containing oil, fuel, hydraulic fluid, or alcohol. When separation is impractical, locate the electric wire above the flammable fluid line and securely clamp to the structure. In no case, should a wire be supported by a flammable CLEARANCE fluid line. 14" MINIMUM
447. HEAT PRECAUTIONS. Separate wires from high temperature equipment, such as resistors, exhaust stacks, heating ducts, etc., to prevent insulation breakdown. Insulate wires that must run through hot areas with a high temperature ANGLE BRACKET WITH insulation material such as asbestos, fiberglas, TWO POINT FASTENING or teflon. Avoid high temperature areas when using cables having soft plastic insulation such as polyethylene because these materials are FIGURE 11.9--Cable clamp at bulkhead hole.
subject to deterioration and deformation at elevated temperatures. Many coaxial cables have this type of insulation. - WIRES LESS THAN 1/d
INCH FROM HOLE EDGE
448. PROTECTION AGAINST CHAFING. Protect wire and wire groups against chafing or abrasion as damaged insulation may result in short circuits, malfunctions, or inoperative equip- GROMMET ment. Support wire bundles using MS-21919 cable clamps as indicated in figure 11.9. When clamped in position, if there is less than 1/4- inch clearance between a bulkhead cutout and the wire bundle, install a suitable grommet as indicated in figure 11.10. The grommet may be cut at 45° angle to facilitate installation provided it is cemented in place and the slot is lo-
however, the following basic principles should be practiced:
o. Make sure all cutting tools used for stripping are sharp.
b. When using special wire stripping tools, adjust the tool to avoid nicking, cutting, or otherwise damaging the strands.
c. Damage to wires should not exceed the limits specified in figure 11.11.
FIGURE 11.11.-Allowable nicked or broken strands.
Wire size Nicked or broken strands Copper AN #22-#12 None #10 2 #8 -#4 14 #2 -#0 12 Aluminum All Sizes None NoTE: Longitudinal scratches in copper wire are not considered cause for rejection or rework.
450. TERMINALS, Terminals are attached to the ends of electric wires to facilitate connection of the wires to terminal strips or items of equipment. The tensile strength of the wire to terminal joint should be at least equivalent to the tensile strength of the wire itself, and its resistance negligible relative to the normal resistance of the wire. Terminals specifically designed for use with the standard sizes of aircraft wire are available through normal supply channels. Haphazard choice of commercial terminals may lead to overheated joints, vibration tailures, and corrosion difficulties.
a. Solder Terminals. For most applications, soldered terminals have been replaced by solderless terminals. The solder process has dis- AC 43.13-1A 1972 solder and become more susceptible to breakage due to vibration.
(5) The wire insulation may be charred during the soldering process.
b. Solderless Terminals. The terminal manufacturer will normally provide a special crimping or swaging tool for joining the solderless terminal to the electric wire. Aluminum wire presents special difficulty in that each individual strand is insulated by an oxide coating.
This oxide coating must be broken down in the crimping process and some method employed to prevent its reforming. In all cases, follow the terminal manufacturer's instructions when installing solderless terminals.
451. ATTACHMENT OF TERMINALS TO STUDS.
Electrical equipment malfunction has frequently been traced to poor terminal connections at terminal boards. Loose, dirty, or corroded contact surfaces will produce localized heating which may ignite nearby combustible materials or overheat adjacent wire insulation to the smoking point.
452. BONDING JUMPER INSTALLATIONS. Make bonding jumpers as short as practicable, and install in such manner that the resistance of each connection does not exceed .003 ohm. The jumper must not interfere with the operation of movable aircraft elements, such as surface controls, nor should normal movement of these elements result in damage to the bonding
a. Bonding Connections. To assure a lowresistance connection, remove nonconducting finishes; such as paint and anodizing films, from the attachment surface to be contacted by the bonding terminal. Do not ground electric wirina dirantle to mamacium nasta
AC 43.13-1A Page 189 1972 FIGURE 11.12.--Stud bonding or grounding to flat surface.
SCREW OR BOLT WASHER A
LOCKWASHER E
• STRUCTURE
WASHER B WASHER C
PLAIN NUT
WASHER D
TERMINAL (LIMIT TO 4) LOCKNUT
LOCKWASHER F Aluminum Terminal and Jumper Struoture Sorew or Bolt and Look nut Plain Washer Woeher Washer C&D Look washer Look washer Aluminum Alloya Cad. Plated Cad. Aluminam Aluminum Cad. Cad.
Steel Plated Alloy Alloy Plated Plated Steel Steel Steel Magnesium Cad. Plated Cad. Magnesium Magnesium Cad. Cad.
Alloye Steel Plated Alloy Alloy Plated Plated Steel Steel Steel Steel, Cadmium Cad. Plated Cad. None None Cad. Cad.
Plated Steel Plated Plated Plated Steel Steel Steel Steel, Corrosion Corrosion Cad. None None Cor. Cad.
Resisting Resisting Plated Resist Plated Steel ¡ Steel Steel Steel Tinned Copper Terminal and Jumper Aluminum Alloys Cad. Plated Cad. Aluminum Aluminum Cad. Cad. Cad.
Rtaal Dlarat A 1100 Platad plate Platad
Page 190 AC 43.13-1A 1973 FIGURE 11.18.-Plate nut bonding or grounding to flat surface.
LOCKWASHER
SCREW OR BOLT WASHER A - LIMITED TO 4
WASHER B
RIVET NUT PLATE Aluminum Terminal and Jumper Struoture Screw or Bolt and Nut plato Rivet Lookwashor Washer & Washer & Aluminum Alloys Cad. Plated Steel Aluminum Alloy Cadmium Cad. plated None Plated Steel steel or alumiaom Magnesium Alloya Cad. Plated Steel Aluminum Alloy Cadmium Cad. plated None or Plated Steel steel or Magnesium aluminum alloy Steel, Cadmium Cad. Plated Steel Cor. Beslet. Steel Cadmium Cad. plated None plated Plated Steel steel or aluminum Steel, Corrosion Corrosion Resist. Cor. Resist. Steel Cadmium Cad. plated Cadmium Resisting Steel or Cad. Plated Steel steel or plated Plated Steel aluminum steel Tinned Copper Terminal and Jumper Aluminum Alloys Cad. Plated Steel Aluminum Alloy Cadmium Cad. plated Aluminam Plated Steal 1 ateal