08 Electrical Features
2022 Cahaba: Chapter 8
General Information
There are two electrical systems in your Cahaba motorhome. These are the 12-volt DC (VDC) system and the 120-volt AC (VAC) system. Most standard appliances require the 120-VAC system, while the majority of the lighting systems used in the Cahaba use the 12-VDC electrical system.
The electrical power for the 12 VDC system is supplied by the batteries of the Cahaba. Those batteries are charged by a power converter. The alternator also charges the batteries when the engine is running.
The electrical power for the 120 VAC is supplied by the 30 AMP shore power cord when the Cahaba is connected to an external power source. The inverter can also supply 120 VAC electrical power (to limited outlets and limited appliances) to the items onboard the Cahaba are powered by the inverter are limited to Televisions and Refrigerator —the inverter transforms the 12 VDC electrical power from the batteries into the 120 VAC electrical power needed for the basic appliances.
To connect the Cahaba to an external source of 120 VAC electrical power, it is first recommended that main 30-amp circuit breaker is in the “off” position. This is done to prevent any power surge upon connecting the motorhome to the external power source. Then unwind the power cord from the electrical compartment located in an external compartment. The standard, flexible, power cord supplied with the Cahaba is designed to handle 30 amperes. Make sure that the pins in the male end of the plug are oriented correctly so they match the power cable, and they are in good condition (i.e., aren’t bent or damaged).
Note: Do not attempt to use any electrical adapters to convert the provided 30amp power cord, as this will damage electrical components inside the motorhome.
If there is a circuit breaker switch at the “plug” end of the power cord, that breaker should be turned “off” before making the connection. Insert the plug into the mating outlet and then turn the circuit breaker “on.” Close and lock the electrical compartment door to protect the contents and to keep them clean and dry. Close the cover on the power box, if so equipped, to avoid an unintentional disconnection and to keep the contents clean and dry. Then switch the main breaker to the “on” position.
Spyder Control System
The Spyder control panel is located on the front shower wall. This panel allows you to control the house lights. This panel also allows you to monitor the holding tank levels and battery condition.
Shore Power
30A 125V SMARTPLUG INLET
The Cahaba utilizes the SmartPlug for shore power. The 30 amp shore power cord can be used to charge the house battery or power the motorhome directly
Note: Do not attempt to use any electrical adapters to convert the provided 30amp power cord, as this will damage electrical components inside the motorhome.
Battery Distribution Center
VOLTA
The Volta energy storage pack (battery) (4X4 ONLY) is located beneath the rear of the Cahaba. This battery can be charged with a shore power connection, a dedicated 6900W alternator, or optional solar panels. The Volta battery has an integrated disconnect. The Volta LCD control panel displays the state of the battery. For more information, please refer to the Volta user manual.
ENERGY STORAGE PACK
The Dragonfly battery (4X2 ONLY) is located under the passenger side bench. This battery can be charged with a shore power connection, a dedicated 6900W alternator, or optional solar panels. The disconnect for this battery is located on the rear of the passnger side bench. A panel located on the front shower wall displays the state of the battery.
Battery Inspection and Care
Volta Battery:
Except for extended periods of storage, no specific maintenance is required for the service life of the
Volta energy storage pack (4X4 ONLY). In the event the Volta energy storage pack has a breach of container integrity or has been submitted to abusive operating situations (crush, short circuit, overcharge, over-discharge, submersion, evidence of combustion or exposure to fire, etc.), contact your authorized Volta representative. Only Volta approved technicians should service a Volta Power Systems energy storage and power distribution system.
Dragonfly Battery:
For the Dragonfly battery (4X2 ONLY), when batteries are not used for an extended period of time, they will gradually lose their optimal electrical charge. Therefore it is necessary to periodically recharge the battery to increase the overall life of the battery. It is also necessary to check the external condition of the battery on a regular basis.
Look for cracks in the battery case and cover. Check the vent plugs and replace them if they are cracked or broke. Keep the battery clean. If any accumulation of dirt or acid residue around the battery terminals may provide an electrical path for battery discharge. The areas around the terminals should be cleaned periodically.
One can use an old toothbrush and a sparse amount of diluted solution of baking soda (sodium bicarbonate) and water (distilled, or deionized is preferred; tap water is acceptable) to clean and neutralize any acidic build up around the battery terminals. If there is any foaming on the top of the battery, this indicates that acidic residues are being neutralized. Rinse the cleaned areas thoroughly with distilled or de-ionized water (tap water is okay as well).
Dry the battery cables and terminals to prevent corrosion; to protect those terminal further, use a plastic ignition spray on the terminals. Do not use grease on the terminals, especially on the metal to metal connections as grease may act as an insulator and keep the battery electrical power from entering the cables.
If the batteries are not going to be used for an extended period of time, they can be removed or the battery cables can be disconnected. IT IS STRONGLY RECOMMENDED that this service be performed by a qualified service technician as this process is complicated and needs to be followed in precise steps. The service technician will mark the positive and negative cables respectfully so they can be properly reconnected when you are ready to put your Cahaba back into service. These batteries will require periodic recharging to maintain their full charge.
Following manufacturer’s recommendations as found in the Owners Information Package, periodically check the batteries to make sure there has been no change in their physical appearance.
WARNING: If the Cahaba ever requires any welding operations on the frame, first disconnect the chassis batteries. Failure to do so will destroy all of the chassis computer systems.
NOTICE: Disconnect the 120VAC electrical power cord and the negative terminal from the coach batteries while working on the Cahaba electrical system.
WARNING: Remove rings, metal watchbands and any other metal jewelry before working around batteries. If any metallic object (tool, jewelry, etc.) contacts the positive battery terminal or any other connection made to that terminal AND also contacts the negative terminal or any of its connections, a SEVERE ELECTRICAL SHORT will occur which could result in an explosion, fire and/or personal injury. Always wear eye projection.
120 – Volt AC (VAC) Receptacles
FIGURE 8-1: 120 VAC
Your Cahaba motorhome is equipped with several 120 VAC receptacles (Figure 8-1) located throughout the interior of the motorhome.
These 120 VAC receptacles are of the “three-prong” variety; the third prong being a grounding pin which provides adequate grounding to protect one from any electrical shock.
For these receptacles to work properly, do not use an adapter, cheater, or extension cord which defeats the function of the grounding pin. For the same reason, never remove or bend away the ground prong or pin from any threeprong AC plug so that it would fit a two-prong AC receptacle (i.e., an ungrounded AC receptacle).
Never operate the Cahaba if there is an electrical short present, as an electrical short may deliver an electrical shock to anyone coming in contact with the exterior of the unit.
If you should feel even the slightest of electrical shock, immediately disconnect the unit from the 120 VAC power source and locate the electrical fault (i.e., typically, it is a break in the grounding circuit).
Do not reconnect the 120 VAC power until after that electrical fault is fixed— the grounding circuit must be continuous from the frame to the distribution panel, to the power cord, and to the earth ground so that electrical-shock protection is realized.
USB Receptacles
The Cahaba is equipped with USB ports conveniently located on the exterior side of the galley and the rear of the DS bench. These ports allow for easy access when charging cell phones, laptop computers, iPods, iPads or other tablets.
Ground Fault Circuit Interupt (GFCI) Receptacles
The Cahaba has two 120 VAC GFCI receptacles (Figure 8-2), which provide greater protection against inadvertent electrical shocks. One is located on the PS bench rear and the other is located on the PS running board rear.
FIGURE 8-2: GFCI RECEPTICLE
These specialized GFCI receptacles provide both overload and shortcircuit protection for the user.
All GFCI-protected receptacles are marked as such, but only one of them may have two pushbuttons on the receptacle (as shown in the picture). The upper pushbutton is a “test” button which can be used to assure that the GFCI function is working—all one need do to test this function is to push that upper button: There will be a momentary “click” and the circuit will be disconnected (i.e., no power is available at the GFCI-protected receptacles). To reset this GFCI breaker, push the lower button (the “reset”)
These receptacles protect the user from ground faults between an electrically “hot” wire and ground. The GFCI will not reduce the shock hazard if the short is between a neutral and “hot” wire, or two “hot load” wires. The GFCI should be tested at least once a month. The 120 VAC electrical system must be “on” for the GFCI to be tested. To test the GFCI the reset button needs to be pushed in fully before starting the test. Push the test button; this will cause the reset button to pop out which means that the protected circuits have been disconnected. Push the reset button back in until a “click” is heard—this will reactivate the protected circuit. If the GFCI is working properly, the reset button will remain in the “in” position.
Inverter
FIGURE: LOW-PROFILE INVERTER
The Cahaba’s Volta system uses a 3200W low-profile inverter (4X4 ONLY).
The 4x2 Cahaba’s uses a 2000W Xantrax inverter. The Xantrax display panel is located on the front shower wall.
Converter
The main converter is integrated into the main load center. The Volta system also uses two DC-DC converters (4X4 ONLY).
Circuit Breakers
The circuit breakers and fuses are installed to protect the electrical system of the Cahaba from any overloads. Do not attempt to change the electrical circuitry or to add appliances yourself.
FIGURE 8-?: MAIN 120 VACPlease consult an authorized Tiffin Motorhomes Dealership or Tiffin Motorhomes, incorporated in Winfield AL to determine whether any changes you desire are appropriate and acceptable. Tiffin Motorhomes’ qualified staff of electricians can readily determine whether any changes sought (e.g. solar, radio, amateur radio, satellite television receiver, personal computer system, and the like) are possible or not and can advise you on how best to realize these enhancements.
The circuit breakers (Figure8-?) are located in the main 120 VAC distribution load center inside the passenger side bench. When the circuit breakers are shut down or electrically tripped, they must be manually reset. As needed, manually reset the circuit breaker or breakers as shown in the accompanying figure.
The panel has a main 30amp breaker which turns off all incoming power to the panel’s branch breakers. All branch breakers are labeled as to their function. This panel also has 12 VDC fuses,
which are labeled as to their function.
Fuses
The electrical circuits protected by the under-dash fuse block include: headlights, panel light for dashboard, tail lights, turn signals, cruise control, engine computer, accessory fuses, heater and dash air conditioning. Additionally, there is another chassis fuse panel which works in conjunction with the chassis fuse panel and provides comparable protection for the above-listed circuits.
Located beneath the access panel on the dashboard are two additional fuse panels; these panels protect the following electrical systems: mirrors, optional satellite jacks, camera, optional power windows, dash trim, lighter, map light, optional power seats, and radio.
Should there be any electrical failure of these components or systems, the first troubleshooting procedure should be to check the fuses and have available replacements to replace any blown fuses, as may be warranted.
As an aid to extracting and/or installing fuses in the fuse blocks, one may wish to buy an inexpensive fuse puller at any electronics or hardware store. This tool makes the installation or removal of fuses much easier and prevents inadvertent damage to nearby fuses or the fuse block itself.
Seven Pin Towing Connector
Your Cahaba is equipped with a standard, 7-pin connector near the towing hitch at the rear of the motorhome to supply the necessary circuitry to control a towed vehicle.
The wiring of that connector is shown in the accompanying diagram (see Figure 8-3)
FIGURE 8-3: seven pin towing connector
Make sure that any cable from the vehicle to be towed is wired correctly to mate properly with the connections shown in the connector. If in doubt about proper wiring, have a qualified service technician prepare and install the necessary cable to mate with the 7-pin connector on the motor home to assure proper operation subsequently when any vehicle is actually towed by the motorhome.
When the towed vehicle is uncoupled from the motorhome and the cable is disconnected from the 7-pin connector, be sure to close the spring-hinged cover plate on the connector to protect the contact pins from dirt or debris. In a similar manner, protect the cable end from similar damage, weather, or debris—one such method could be to place the connector end in a heavy-gauge plastic bag (e.g., polypropylene, polyethylene, etc.) and secure the bag tightly around the cable with a stout elastic band or tape and then mount the secured cable in a manner to keep it both from mechanical damage and water intrusion.
When the towed vehicle is again coupled to the motorhome via the towing hitch and the cable is again connected to the 7-pin connector, make sure the resultant connection is tight and solid so that the connection won’t jar loose during use. Several supplemental methods to secure that connection have been used; some of which include securing the connection with a strong rubber band or with velcro type fasteners to provide a supplemental mechanical backup to the actual electromechanical connection. Should a conversion adapter to convert the round, seven-pin connector to a flat, four-pin connector be needed; such an adapter may be purchased from any RV after-market store.