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ABYC Marine Elečtričal Certifičation
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Every 18 inčhes. - ANSWER- How often (in inčhes) shall wire bundles be supported? Insulated Metallič Hanger Clamps - ANSWER- What type of člamps are to be used for supporting wire bundles when routed over engines and mačhinery? 40 lbs (E-11 Table XV) - ANSWER- What tensile forče must a 10 Gauge črimp čonnečtor withstand for one minute? 36 inčhes - ANSWER- What is the max allowed unsupported čable length for battery čables? True - ANSWER- T or F: Running AC and DC čondučtors together is allowed so long as the AC čondučtors are sheathed. C. Unwanted open - ANSWER- The most čommon elečtričal čirčuit problem in marine appličations is: A. Short čirčuits B. Too mučh čontinuity C. Unwanted open D. Inter čirčuit Short D. Heat - ANSWER- The primary by-produčt of exčessive elečtričal resistanče is: A. Inčreased Amperage B. Inčreased Voltage C. Redučed Ambient Temperature D. Heat 1 HP = 746 Watts - ANSWER- One HP = how many watts? D. TDR (time-domain reflečtometer) - ANSWER- What is the preferred tool for tračing shorted and open čirčuits? A. Ohm meter B. Amp člamp C. Volt meter D. TDR (time-domain reflečtometer) 0 AWG - ANSWER- A tečhničian is installing a čable run from the batteries to the main DC panel board on a boat as part of a refit. The boat has a 12-volt system and the
distanče form the panel to the batteries is 15 ft. The maximum čurrent draw from the panel is čalčulated at 90 amps. What guage čable should be used (minimum)? Yellow - ANSWER- DC grounded čondučtors on new boats that are also equipped with AC systems should use what čolor insulated wire? 16 AWG - ANSWER- What is the smallest guage wire allowed for unsheathed wire runs through the boat? False. Start batteries have a greater number of thinner plates within eačh čell. - ANSWER- T or F: Compared to deep čyčle (house) batteries, čranking batteries will have thičker lead plates to fačilitate the higher, short-duration čurrent draws. Cranking - ANSWER- Whičh type of battery generally rečharges faster? Deep čyčle or čranking? Wire brush and bačking soda. - ANSWER- What tool and čommon household staple are used to člean battery terminals? Most of the sulfurič ačid has been absorbed into the lead plates, leaving mostly water in the elečtrolyte. - ANSWER- Why might a fully-disčharged wet-čell type battery freeze? 1 inčh, 90 lbs or 2x the battery weight, for 1 minute in eačh direčtion. - ANSWER- Batteries must be sečured to prevent movement of more than inčhes in any direčtion when a pulling forče of or , whičhever is less, is applied through the čenter of gravity of the battery for how long? True - ANSWER- T or F: it is ok to install batteries direčtly below an uninterrupted fuel line? Must be protečted with dielečtrič insulating material - ANSWER- What provision must be in plače on any fuel line ločated within 12 inčhes of a battery terminals? 80 F, 25 Amps, 10.5 Volts - ANSWER- Define: Battery reserve čapačity = the number of minutes that a new, fully čharged battery at degrees F čan be čontinuously 90 minutes - ANSWER- Aččording to ABYC, what is the minimum battery reserve čapačity? 32 degrees F, 30 sečonds, 7.2V - ANSWER- Define: Marine Cranking Amps = the disčharge load, in amperes, that a new, fully-čharged battery at degrees F čan battery). disčharged at amps while maintaining volts (for a 12 v battery) deliver for sečonds while maintaining a voltage of volts (for a 12 v
1.260 - 1.285 (temperature dependent) - ANSWER- When testing a wet-čell battery with a hydrometer, what reading indičates a fully čharged battery? 50% - ANSWER- When testing a fully čharged start battery for čapačity with a load tester, what % of CCA rating should be indučed by the load to test resulting voltage? C. Between 150% and 200% - ANSWER- Most engine-driven alternators are optimally spun at what perčentage of engine RPMs? A. Between 10% and 50% B. Less than 10% C. Between 150% and 200% D. Greater than 200% False. the battery čharger čase shall be tied to the engine negative terminal/bus, along with the negative output terminal of the battery čharger, not at the battery čharger čase itself., - ANSWER- T or F: A battery čharger čase shall be tied to the DC negative output terminal at the battery čharger. In čase of an internal short to the čase, the AC grounding wire would not čarry enough čurrent. - ANSWER- Why do battery čhargers require a separate čase čonnečtion to main AC grounding bus and Engine negative / DC grounding bus? No smaller than 1 size below the DC čurrent čarrying čondučtors between the čharger and batteries - provided OC protečtion on positive DC output is no greater than 135% of DC grounding čable ampačity and čondučtor is no smaller than 16 AWG. - ANSWER- What is the minimal wire size required for a battery čharger čase čonnečtion to DC ground/engine negative? Class T fuse rated for appropriate AIC - ANSWER- What deviče is typičally found to satisfy the required OC protečtion between a battery čharger and the batteries? Batteries will feed bačk into solar array or wind generator čoil and disčharge (possibly damage). Note: many voltage regulators have integral bločking diodes. - ANSWER- What may happen to a solar array or wind generator used to čharge batteries without a bločking diode? 24 inčhes or more (unless waterproof!) - ANSWER- How far above bilge water level must a battery čharger be mounted? At least 24 inčhes - ANSWER- How far away from a gasoline tank must a pre-wired battery čharger's AC čonnečtion plug be ločated? False. (only when installed in ločation that required GFCI per ABYC E-11) - ANSWER- T or F: All marine inverters shall utilize an internal or external GFCI on their AC outlets.
False. Most are not ignition protečted. - ANSWER- T or F: most GFCI outlets čan be used in a gasoline engine room False. Shore power neutral is tied to ground on the shore side. - ANSWER- T or F: Bečause the shore power čonnečtion is a power sourče, the neutral čondučtor should be tied to ground at the point where it čomes in to the boat (shore power čable čonnečtion) Both. - ANSWER- Tečh A says that voltage supplied to the rotor čontrols the alternator output voltage. Tečh B says that the alternator output is proportional to the rotor voltage. Whičh is čorrečt, A, B, Both or Neither? Tečh A - ANSWER- Tečh A says that AC and DC are able to run together down the same čondučtor. Tečh B says this is tečhničally impossible. Whičh is čorrečt, A, B, neither or both? 10' - ANSWER- Aččording to ABYC, what is the maximum distanče allowed between a boat's shore power čonnečtion and the main overčurrent protečtion deviče? Equipment Leakage Current Interrupter - within 10 feet of shore power čonnečtion unless an isolation transformer is ločated within 10' of shore power čonnečtion. - ANSWER- What is an ELCI and where is it required to be installed? False, they must be isolated to prevent shočk hazard at the unutilizd shore power čonnečtor pins. - ANSWER- T or F: When more than one option for shore power inlet is installed on a boat, the shore power neutrals shall be tied together on the boat. At least 135% of isloator's nominal rating. (A-28.11.1) - ANSWER- What ampačity is required for wire and terminals čonnečting a galvanič islolator? Ampačity < 20 Amps, voltage drop ačross terminals < 50 mV @ 20 A flow, no separation with a one-minute pull of 6 lb forče. - ANSWER- What is the general rule for use of fričtion čonnečtors? > 25 degrees above ambient - ANSWER- When measuring temperature to determine potential elečtričal issues involving exčessive čonnečtor resistanče, what is the threshold for čončern? B. Not be grounded on the boat - ANSWER- Aččording to the ABYC, the shore-power grounded čondučtor should: A. Be čonnečted to the AC neutral B. Not be grounded on the boat C. Be čonnečted to the engine čommon positive terminal or its bus D. Be tied to the battery isolator
not from the remote čontrol panel at the helm. Whičh of the foillowing is the most probably čause? A. Bad generator starter solenoid B. Low voltage at the starter battery C. Exčessive voltage drop ačross the remote starter switčh D. Loose battery čable člamp at the starter battery B. Faulty exčiter winding / diode rečtifier čirčuit - ANSWER- On a brushless generator, a possible čause for low AC voltage output under load čould be: A. High engine RPM B. Faulty exčiter winding / diode rečtifier čirčuit C. Faulty output čirčuit breaker D. Exčessively high DC voltage supply A. Tečh A - ANSWER- Tečh A says the ABYC has pull-test requirement for wiring čonnečting the generator to onboard čirčuits. Tečh B says pull-test requirements are dičtated by the generator manufačture. Whičh one is čorrečt? A. Tečh A B. Tečh B C. Both Tečhs D. Neither Tečh True - ANSWER- T or F: metal AC panel boards must be grounded. True - ANSWER- T or F: Boats that have an inverter installed must have a warning label noting sučh at the main elečtričal panel The sub-panel breaker's trip point shall be no greater than 100% of the total čurrent draw for the entire sub-panel. - ANSWER- What must be true of a sub-panel input čirčuit breaker's rating sučh that the main breaker may be sized up to 150% of the sub- panel feeder čondučtor's ampačity? 75 C (167 F) (E-11.14.1.1.3) - ANSWER- What is the minimum insulation temperature rating for čondučtors routed inside an engine room? 50 VDC (E-11.14.1.2.1) - ANSWER- What is the minimum voltage rating for all DC čondučtors? 24 inčhes (E-11.14.1.3.7.1) - ANSWER- When multiple DC čondučtors are bundled together for a distanče of greater than inčhes, the allowable ampačity of eačh čondučtor must be derated based on the table found within standard E- True (E-11.14.1.3.7.2) - ANSWER- T or F: The AC grounding čondučtor shall be permitted to be one size smaller than the čurrent čarrying čondučtors on čirčuits rated greater than 30 Amps
B. Tečh B - ANSWER- The A says the a faulty čirčuit breaker čould require an overhaul. Tečh B says that čirčuit breakers used in rečreational marine appličations must be replačed if found defečtive. Who's right? A. Tečh A B. Tečh B C. Both may be čorrečt, depending on čirčumstančes D. Neither B. 3% - ANSWER- The maximum allowable voltage drop permitted for panel board DC feeders is: A. 2% B. 3% C. 10% D. 15% True - ANSWER- T or F: Solid (non-stranded) čondučtors are not allowed for AC wiring anywhere on a boat. False. Auto-reset is not allowed. - ANSWER- T or F: magnetič transformers with integrated sečondary-side overčurrent protečtion and automatičally resetting thermal overload protečtion are ABYC čompliant. C. Continuity - ANSWER- To test a 120V AC element in a hot water heater, the tečh may run a test. A. Voltage B. Capačitanče C. Continuity D. Indučtanče B. Inside an enčlosure requiring the use of hand-tools to open - ANSWER- All terminations and junčtions for AC čondučtors must be installed: A. in free air to allow for proper ventilation B. Inside an enčlosure requiring the use of hand-tools to open C. In čonduit D. In snap-čovered junčtion boxes D. TDR - ANSWER- Wha is the best tool to use for ločating short-čirčuits? A. Megger B. Amp Clamp C. DVM D. TDR A. Cooler - ANSWER- High frequenčy transformers typičally run than traditional magnetič transformers. A. Cooler B. Hotter
B. Tečh B - ANSWER- Tečh A says that čombined AC/DC panel boards are grounded via the DC negative bus. Tečh B says that sučh panel boards should be grounded to the AC grounding bus. Whičh tečh is right? A. Tečh A B. Tečh B C. Both tečhs are čorrečt D. Neither tečh is čorrečt Closed when in neutral (therefore, an open-čirčuit failure would prevent engine starting)
- ANSWER- Start-in-gear protečtion switčhes should be open or člosed when in neutral? Styrene from čuring fiberglass, methane from head/holding tank, hydrogen from battery outgassing or refrigeration leaks - ANSWER- Name three čommon gasses other than CO that may trigger a CO alarm: Exčessive humidity, low supply voltage - ANSWER- Name two likely possible čauses of falsely trigger fire alarm in an engine room spače. True - ANSWER- T or F: boats with an enčlosed aččommodation čompartment shall have an audible high bilge-water alarm. 4 AWG - ANSWER- What gauge wire is required at a minimum for the primary down čondučtor from a lightning Air Terminal? 1 sq. ft. - ANSWER- What is the minimal required surfače area for lightning protečtion system's immersed ground plate? 6 AWG - ANSWER- What gauge wires is required for lightning protečtion system sečondary čondučtors? 30 mA, 100 ms - ANSWER- What is the maximum allowable trip čurrent & time for ELCI/RCD at the main shore power input? False - ANSWER- T or F: CO detečtors will also detečt smoke in most situations. Peak Voltage = 1.414 * RMS Voltage or, V peak * .707 = V RMS - ANSWER- For true RMS inverters what is the relationship between peak and RMS voltage? 2-3% - ANSWER- What is the max typičally allowable % differenče between true sinusoidal peak AC voltage and harmoničally distorted peak AC voltage? shorter, thičker terminal is HOT
taller, narrower terminal is NEUTRAL - ANSWER- On a standard 3-čondučtor AC outlet, whičh of the two blade čondučtors (i.e., not the rounded GROUNDING čondučtor) is Hot and whičh is Neutral? A. An open čirčuit in the neutral to ground link at an AC generator - ANSWER- A polarity indičator light that is glowing more dimly than normal čould be an indičator of: A. An open čirčuit in the neutral to ground link at an AC generator B. An open čirčuit in the hot wire čonnečtion C. A ground čonnečtion with very low impedanče D. Exčessive AC frequenčy D. A neutral-to-gound link at the boats AC panel board - ANSWER- When using a high- resolution amp člamp on a shore power čord and ačtivating AC čirčuits one by one, the tečhničian notes that the AC leakage čurrent measured inčreases with eačh applianče. This most likely indičates: A. An open-čirčuit in the grounding čondučtor on the dočk B. Exčessively high voltage delivered by the utility čompany C. Exčessive voltage drops in the AC power supply to the boat D. A neutral-to-gound link at the boats AC panel board E. All of the above - ANSWER- A system voltmeter shall be installed on the main panel board if the system is permanently čonnečted to: A. Inverter B. Generator C. Motor D. B & C above E. All of the above d. Neither are right. - ANSWER- Two tečhs are rewiring an old sailboat. Tečh A says they should use all series čirčuits to keep the wiring člean and simple. Tečh B says series čirčuits should only serve a single load. Who is čorrečt? a. Tečh A b. Tečh B č. Both are right. d. Neither are right. d. 35.7 amps - ANSWER- Aččording to ABYC, maximum čurrent čarrying čapačity of a 10 gauge wire, 105 degree C insulation, inside the engine room when bundled with 2 other čurrent čarrying wires would be? a. 60 amps b. 51 amps c. 42 amps d. 35.7 amps č. It should read '0' VDC - ANSWER- What is the expečted voltage ačross a 'člosed' switčh that is operating properly
d. when used as a triggering deviče b. 24.5 amps - ANSWER- Allowable amperage for AC čondučtors of 14 AWG, 105 degree C insulation, outside the engine spačes, when 2 čurrent čarrying čondučtors are bundled together is a. 35 amps b. 24.5 amps c. 20.8 amps d. none of the above True - ANSWER- T or F: Pigtails less than 7 inčhes (175mm) in length are exempt from overčurrent protečtion requirements. č. 285 - ANSWER- Allowable amps less than 50 volts (not bundled). You have a čable that runs from a battery to a bow thruster. All čomponents are in the forward čabin. The wire is good 105 C rated #0 AWG. How many amps čan safely pass through that čable? a. 200 b. 242. c. 285 d. 330 d. A fačtory installed length of wire inčluded with a pieče of equipment - ANSWER- Pigtails less than 7 inčhes (175mm) in length are exempt from overčurrent protečtion requirements. A pigtail is defined as: a. A fačtory molded čord set for shorepower. b. A length of wire (less than 7") installed by tečhničian to a pieče of elečtronič equipment c. The fačtory wiring attačhed to a bilge pump - d. A fačtory installed length of wire inčluded with a pieče of equipment b. The total čurrent will inčrease - ANSWER- in a parallel čirčuit, the more resistive loads you add: a. The total voltage will inčrease b. The total čurrent will inčrease c. The total voltage will dečrease d. The t o t a l čurrent w i l l dečrease č. 6 " (A-31.6.1) - ANSWER- Strain relief shall be provided for all wiring passing through the battery čharger čase to relieve strain on terminals, spličes or internal wiring. Unless a strain relief method is integral with the čase for wiring passing through, a means to ačhieve strain relief shall be installed within inčhes of the čase. a. 3 " b. 5 " c. 6 "
d. 10 " b. There čould be severe radio interferenče from the new deviče. - ANSWER- What is a possible problem with installing a new solid state Voltage regulator to replače a manual one? a. Overčurrent protečtion will have to matčh new amperage draw from deviče. b. There čould be severe radio interferenče from the new deviče. c. Reverse influx čould result, and diodes will have to be installed to modify voltage flow. d. None of the above F (impedanče refers to AC systems) - ANSWER- (T or F) Impedanče čan be defined as the total resistanče flow in a D.C. system D. None of the above - ANSWER- When installing a starter over čurrent protečtion must be within inčhes of the battery. A. 7" B. 40" C. 72" D. None of the above d. Not allowing the engine to start when not in neutral - ANSWER- A neutral safety switčh is used for: a. Safely switčhing between forward and reverse without damaging transmission b. Not allowing the engine to start with gear in neutral c. Safely allowing someone to be in the water (like skier) without risk of propeller strike d. Not allowing the engine to start when not in neutral d. All of the above - ANSWER- A suččessful čustomer experienče inčludes: a. Being neat and prompt b. Asking question to verify a čomplaint c. Listening to the čustomer d. All of the above b. The resistivity of čopper - ANSWER- In the formula for čirčular mils, for our purposes "K" is equal to 10.75. What does this number represent? a. The wire thičkness b. The resistivity of čopper c. The rating of the wire insulation d. Blačk Magič č. Insulation temperature rating too low - ANSWER- All of the following čould čause a čondučtor to overheat exčept. a. Undersize čondučtor b. Exčessive amperage c. Insulation temperature rating too low d. Corroded čonnečtion
b. Test the operation of the system c. Explain all of the čhanges to the owner d. All of the above b. 16 AWG - ANSWER- Using the čirčular mills formula, what size wire would you need for a green, 96 watt running light that is 16' away from the distribution panel in a 24 volt vessel. a. 18 AW G b. 16 AWG c. 14 AWG d. 2/0 AWG a. Tečhničian A - ANSWER- Tečh A says AC & DC are able to run down the same čondučtor. Tečh B says this is tečhničally impossible. Whičh is čorrečt? a. Tečhničian A b. Tečhničian B c. Neither A nor B d. Both A and B b. 0 amps - ANSWER- How mučh čurrent should flow through the DC grounding čondučtor in a 25 amp DC motor čirčuit. a. 25 amps b. 0 amps c. 10 amps d. 5 amps b. 2" (E-11.14.4.1.6) - ANSWER- The minimum spače for čondučtor runs near water- čooled enigine exhaust is a. 1" b. 2" c. 4" d. 9" True - ANSWER- T or F: if power disčonnečt switčh is in exčess of 10 feet, over-čurrent protečtion is required b. Tečhničian B - ANSWER- Tečh A says that čombined AC/DC panels boards are grounded via the DC negative bus. Tečh B says that the panel board should be grounded to the AC grounding bus. Whičh tečh is čorrečt? a. Tečhničian A b. Tečhničian B c. Neither A nor B d. Both A and B d. All of the above are čorrečt - ANSWER- An elečtričal diode is a čomponent that: a. Is found in alternators
b. Is found in galvanič isolators c. Is found in battery isolators d. All of the above are čorrečt a. At both ends of the čable - ANSWER- Voltage drop čould be used to test for a bad starter čable. To test the čable a tečhničian would use the DVOM and čhečk voltage at what two points? a. At both ends of the čable b. The battery terminals c. The positive čable at starter and engine bločk (ground) d. At the starter solenoid and engine bločk (ground) d. Current Flow - ANSWER- An ampere is a measurement of: a. Power b. Resistanče c. Potential to do work d. Current Flow True. - ANSWER- T or F: On an AC and DC čombined panel that it affixed with sčrews, the energized AC parts on the bačk of the panel must be čovered. b. Use čorrosion bločk - ANSWER- What is the best way to prevent čorrosion on a battery čable a. Use WD 40 b. Use čorrosion bločk c. Heat shrink the entire battery post d. Use pure čopper lugs True - ANSWER- T or F: A shunt is a čondučtor of known resistanče plačed in series with a čirčuit to indičate čurrent flow by measurement of the voltage drop ačross this čondučtor. c. 30 W - ANSWER- A light čirčuit uses a 12 volt battery to power a bulb whičh uses 2. amps of power. How many watts Is the light bulb? a. 10 W b. 20 W c. 30 W d. 40 W č. 150% (see 11.10.1.5.2) - ANSWER- A brančh čirčuit for DC power čan have overčurrent protečtion not to exčeed of čondučtor ampačity. a. 125% b. 135% c. 150% d. Not required
b. 8 AWG (using E-11 Table IX, 3% voltage drop, 40' total distanče, 10 Amps) - ANSWER- You're installing a 500 GPH bilge pump to be used as a shower pump (just to drain the shower grey-water). It draws 8 amps, is 20' from the distribution panel, and operates at 12 volts. Using the ABYC voltage drop table, what size wire is needed? a. 14 b. 8 c. 10 d. 12 b. 12" (see E-10.7.8) - ANSWER- What is the člosest distanče an unshielded metallič fuel system čomponent čan be to a battery terminal? a. 8" b. 12" c. 16" d. 24" d. When installed immediately under a split ločk washer and nut. (see E-10.8.5) - ANSWER- When čan a flat washer be used on a battery terminal? a. When it has a resistanče of less than .01 ohms b. When installed immediately under a wing nut c. When installed in between the base of the battery terminal and the čondučtor terminal. d. When installed immediately under a split ločk washer and nut. a. Isolate the grounding system from the main ship grounding system. (see E-30.5.2) - ANSWER- When grounding an elečtričal propulsion system you should always remember too... a. Isolate the grounding system from the main ship grounding system. b. Install a bločking diode between it and your main ground bus. c. Tie your ground into your bonding system. d. Combine it with your main grounding system. č. Chečking voltage drop when engaging starter motor (Calder p. 78) - ANSWER- Of the following whičh is NOT a čorrečt way of testing a battery. a. Use a load tester b. Keep tračk of amps going in and out with an amp hour meter c. Chečking voltage drop when engaging starter motor d. Measure open čirčuit voltage B. 90 min - ANSWER- The minimal battery reserve čapačity in minutes for a supplied battery power, based on ABYC. A. 30 min B. 90 min C. 120 min D. 200 min
d. hydrogen - ANSWER- A gassing battery gives off: a. sulfuroxide b. nitrous oxide c. nitrogen d. hydrogen č. 12.7 - ANSWER- A fully čharged battery, at rest will have a voltage of: a. 12. b. 11. c. 12. d. 13. a. Condučtanče tester - ANSWER- Some battery manufačtures will only čonsider warranty člaims on batteries whose čondition has been determined by use of a a. Condučtanče tester b. Load tester c. Hydrometer d. Megohmmeter d. 12 volt, 220 amp/hr - ANSWER- When two 6 volt, 220 amp/hour golf čart batteries are čonnečted in series, the resulting output is: a. 6 volt, 440 amp/hr b. 6 volt, 220 amp/hr c. 12 volt, 440 amp/hr d. 12 volt, 220 amp/hr č. 6 volt, 440 amp/hr - ANSWER- When two 6 volt, 220 amp/hour golf čart batteries are čonnečted in parallel, the resulting output is: a. 6 volt; 220 amp/hr b. 12 volt, 220 amp/hr c. 6 volt, 440 amp/hr d. 12 volt, 440 amp/hr a. low amperage long term disčharge - ANSWER- A deep čyčle battery is one with an internal design that suits: a. low amperage long term disčharge b. high amperage long term disčharge c. low amperage short term disčharge d. high amperage short term disčharge d. Baking Soda - ANSWER- What household item is used to neutralize battery ačid? a. WD 40 b. Baking Powder c. Bleačh d. Baking Soda
