Association Forum - Hull 922 - Catalina 250 Electrical Upgrade

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

Catalina 250 Specific Forum

Hull 922 - Catalina 250 Electrical Upgrade

New Topic

Topic Locked

Printer Friendly

Author

Topic

Carl in LA
Captain

Member Avatar

USA
284 Posts

Initially Posted - 06/01/2018 : 22:22:33

Catalina 250 Electrical System Upgrade

(a bit lengthy for a forum post... if you would like to see a photo of a specific improvement please ask and I'll post)

Backstory

A year ago, in June 2017, my wife and I, after six months of ownership, made our first weekend cruise on the new to us 2007 Catalina 250 �Island Dreams�. Island Dreams came to us as an unmolested good condition stock boat with basic equipment and systems provided by the factory. A VHF radio, stereo, and Raymarine Speed/Depth meter, cockpit table, marine head and holding tank, a shore power 110-volt service with a circuit breaker switch and two outlets and a ProSport12 battery charger were the only modifications to the boat.

Existing situation

Over the course of the weekend cruise we learned that three primary limitations to an enjoyable cruising weekend would need to be addressed: holding tank capacity, fresh water capacity, and refrigeration. While not necessary it was also agreed that a microwave oven would be a helpful addition to the galley.

Holding tank capacity was addressed by switching out the water based marine head for a dry composting toilet procured from C-Head. The C-Head is a stand alone unit providing relatively long durations of use before reaching solids storage capacity. Liquid waste is captured in one gallon plastic jugs which must be frequently emptied, which in the case of Island Dreams means continued use of the holding tank but at a much lower rate, providing for perhaps a week of storage capacity before the tank would need a pump out. The problem of holding tank capacity was solved by installation of the C-Head.

At this time fresh water capacity is still unresolved although plans are underway for installation of a second tank that will double storage capacity.

Refrigeration, and the necessary electrical infrastructure to support compressor based refrigeration have been addressed. Refrigeration onboard is now provided by a Norcold NRF 30 portable electric refrigerator/freezer. The Norcold is essentially the same size as the ice box it replaced and fits in the space provided in the galley on the Catalina 250. The Norcold is a compressor based refrigeration device with capability to maintain desired temperatures down to -5-degrees fahrenheit. The Norcold NRF 30 requires about four amps of power when running and on average consumes about two amps per hour by cycling on and off. The ability for the boat to provide the Norcold�s 48-amps per day of power calls for a robust 12-volt electrical system.

Parameters and Limitations

In this era it is well understood that solar panels and battery electrical systems can provide enough power to support refrigeration as well as most other electrical demands on board a small sailboat. In solar/battery installations bigger is generally better. Unfortunately, on the Catalina 250 there is not much room for mounting solar panels and storage batteries.

For Island Dreams, the process began by establishing a daily power budget and back-calculating through the limitations of lead/acid battery drawdown capacity and solar panel power delivery capacity. In the case of Island Dreams, on paper, the electrical system would require about 400-amps of battery capacity and 400-amps of solar panel capacity. At the current state of lead/acid battery and solar panel technology these power levels are barely achievable and the system as installed is not sized as such.

Planning and Procurement

Typical sailboat solar/battery installations have solar panels mounted on cabin tops and bimini tops with batteries located below the waterline in holds. The installation on Island Dreams follows this model. The bimini top on Island Dreams has room for three or four 100-watt solar panels. Lightweight flexible solar panels were chosen to minimize weight high above the waterline. Thankfully, there are few rigging parts that will cast shadows aft on the boat.

Flexible solar panels are a relatively new item in the marketplace with some reported failures of early products. For Island Dreams, initially, two AllPowers ETFE coated 100-watt panels are used. Space and mounting fixtures are provided for a third panel and with mounting reconfiguration a fourth could be added.

Typical sailboat solar/battery installations use lead/acid batteries and generally use six-volt �golf cart� batteries. A 12-volt system would require two six-volt batteries wired in series to provide 12-volts. Golf cart batteries typically provide about 220-amp hours of power capacity. The designed system would require four batteries to achieve 400-amps storage capacity. The batteries procured for Island Dreams are Exide GC-135 which are rated for 226-amps at the 20-hour rating.

Microwave ovens run on 110-volt power which, on Island Dreams, is achieved by transforming the 12-volt source power to 110-volt by means of an inverter. The inverter has to be sized to the expected load and provide some reserve capacity. A small 700-watt microwave was procured. For Island Dreams a Samlex 1500-watt sine-wave inverter is suitable and is capable of powering the microwave. The Samlex 1500-watt inverter also comes with a remote control switch allowing the inverter to be located in a less accessible location.

An inverter is a helpful device as it allows for bringing onboard 110-volt devices such as power tools, computers, and battery chargers. The inverter is the most power hungry device on the boat�s electrical system with recommended capacity allowing for 150-amp power draw during the most demanding use. Even for short cable runs such large draws require heavy cable and fixtures along the electrical path. In case of Island Dreams the inverter required 1/0 cable - about a half inch thick cable.

Cable size is also a concern for the solar panel installation. In a marginal installation on a small boat consideration has to be made for any voltage drop that would occur over the length of cable from the panels at the bimini to the batteries down in the holds. The roughly 25-foot run between the panels to the batteries required 4-AWG cable.

A Blue Sky Solar Boost 3000i MPPT solar controller provides power management for the solar power and battery charging. The controller is sized to the system and the MPPT feature maximizes power conversion.

With the availability of additional power, additional conveniences are being installed including meters, power outlets, fans, and water pumps. Installation of all the additional devices require several switches, switch panels, busses, fuses, and cables. Cable sizes and fuse sizing has to be considered for each circuit use.

In order to inventory the new system a wiring diagram was prepared.

The existing 12-volt Catalina 250 electrical system consists of a Group 24 12-volt battery located aft and a six circuit panel delivering power to navigation lights, convenience cabin lighting, foredeck lighting, as well as power to electric start the Honda outboard motor. The Honda outboard has an alternator and can provide perhaps 8-amps power back to the system.

The new system system shifted power supply for the existing Catalina panel from the aft Group 24 battery to the new golf cart house batteries. With the new system the Group 24 battery is basically a starting battery for the Honda outboard and provides power to the Raymarine ST2000 Autotiller. Battery switches allow combining the systems such that the Honda outboard can provide power to the overall system but this not the normal operation mode. The Blue Sky solar controller provides an auxiliary 2-amp charging circuit which is wired to the Group 24 battery.

Installation

Space is somewhat limited on the Catalina 250 and building the electrical distribution system in the Starboard settee hold was deemed the best location for the build. A separate panel was installed for the Samlex remote switch, the Blue Sky controller, a small switch panel, and meters. The second panel was installed above the settee on the Starboard side forward of the galley.

Common HDPE white plastic board was used for both the upper and lower panels. On the upper panel cutouts were made to flush mount the devices. Devices are mounted directly to the HDPE on the lower panel. Devices generally serve the following functions: Solar power management, battery charging, fan circuits, pump circuits, and outlet circuits.

A cardboard battery mock-up revealed that there would be sufficient room in the settee holds for four golf cart batteries by placing two batteries on either side of the boat. The vertical clearance was very tight when allowing for a plywood base. The plywood bases are fixed to the inner liner of the boat and provide a hard location for secure battery mounting straps.

The battery mounting location is a concession as the batteries are not contained in battery boxes. There is a concern of the batteries off-gassing vapors. A battery box installation would be more desirable but space in the settee holds does not allow for such. A concession was to install stainless steel ventilators on both sides of the settee holds.

Cables are generally routed between the hull and inner hull liner. Cables from the solar panels are routed along the bimini frame to an access point along the starboard gunwale. Inside the boat the solar panel cables are routed inside the cavity between the liners forward behind the galley to the starboard settee hold. Cables serving the Group 24 starting battery are routed between the hull liners. A 12-volt power outlet cable goes forward to the forepeak for an outlet. Cables go across the hull to the port side of the boat for head fans and a washdown pump. Cable pulling was performed by telegraphing pull cords through the hull. Holes were drilled through bulkheads as necessary for routing of cables.

The ProSport12 battery charger was previously mounted on the aft bulkhead. The charger is now relocated to the starboard settee hold. Relocating the charge to the hold is a concession. Instructions for the charger state that the charger should not be placed in the same hold as the batteries. 110-volt power was carried forward from the circuit breaker to power the battery charger.

The Samlex 1500-watt inverter is mounted in the hold below the galley. An inverted 110-volt circuit is routed to an outlet at the galley and then a continuation of the conductor is routed aft to serve the microwave.

A washdown pump is mounted in the hanging locker aft of the head. The washdown pump receives its seawater from the abandoned seacock which previously served the marine head. The pressure side of the washdown pump is routed to the port side of the cockpit terminating in a hose bib mounted to the lower cockpit face. An on/off switch for the pump is mounted down low on the forward face of the aft berth - near the hand hole opening which allows access to the raw water seacock. The fuse for the washdown circuit is located on a fuse block on the distribution panel.

Two fans operate in the head. One fan on a mechanical timer switch operates a small in line �computer fan� which evacuates air from the C-Head container. The C-Head is vented to the outside on the starboard side of the boat through a small tank vent. The second fan in the head is a Guest personal fan and wall mounted on the starboard face above the sink. The fan provides air circulation in the head. The Guest fan is controlled by a Pulse Width Modulator (PWM) switch allowing a wide range of fan power as needed.

Two additional fans are accounted for in the circuits� a fan to be mounted far aft serving the aft berth and a fan far forward serving the cabin. The fans will be installed as needed in the future.

The solar panels are mounted to �flexible� 1-inch aluminum tubing above the bimini. The tubing is mounted to sliding fixtures on the horizontal rail of the bimini frame. The tubing is split left/right at the middle of the span across the bimini. The intent is that by moving the support tubbing forward and/or aft the angle of the solar panel may be shifted to better match the angle of the sun at that particular time. Matching the angle of the panel to the sun increases power generation.

Operation

The system is intended to be self sustaining. The general operation is for the battery selector switch to stay to the house side and operate all devices. The solar power feed is switched although it is intended to remain in the closed position for continuous supply when generating power. A cautionary note - the solar controller can be damaged if solar power is supplied while house power is turned off. As such there is a reminder note on the battery switch and a piece of tape restricting switching pending turning off the solar power switch.

The ProSport12 charger is not expected to be used. The presumption is that over the course of the life of the batteries sufficient power will be generated by the solar panels to sustain the system. The ProSport12 charger is connected and operational should the need for use arise.

As the system is a new install and its performance is untested. The solar controller, with two 100-watt panels may be able to put maybe 12 to 15 amps per hour into the system with good sunshine on the solar panels. Assuming a full daily load of 60 or so amps have been drawn from the batteries that amount would be replace in just four hours. But it�s not clear how the system will perform when there are several cloudy days in a row minimizing power replacement.

Revisions

Anticipated revisions include a likely relocation of the ProSport12 charger out of the hold to another location, procurement of a third AllPower 100-watt solar panel, and two additional golf cart batteries. The support system for the solar panels will need a revision to strengthen the junction between the left and right halves of the tube. At present the junction is made by a piece of plastic conduit slipped inside the 1-inch aluminum tubing - the conduit does not appear to have the strength necessary to support the panels at various angles.

Review

The electrical upgrade to Island Dreams was a relatively expensive and labor intensive effort. Some may argue that the work is being done on the wrong boat� The Catalina 250 may be best suited for day sails and situations where using a quality ice chest would suffice for refrigeration. Could be true. It does feel that the cruise capable electrical system is somewhat shoe-horned into the boat. The electrical conveniences are appreciated. The ability to quickly microwave a cup of coffee is appreciated. The fans moving air are appreciated. And an electrical system does all these things with silent and clean solar power is greatly appreciated. Adding the extra weight of golf cart batteries and heavy cable does not appear to diminish the sailing performance of the boat - although the boat sits just a bit lower in the water.

Every boat is a compromise and by installing a cruising electrical system, Island Dreams has diminished some of the compromises necessary to cruise a small boat.

Catalina 250 - Pretty Good Boat

Lehooks
Deckhand

Members Avatar

USA
11 Posts

Response Posted - 08/25/2018 : 16:32:13

Carl, great post. Very well thought out
1) Why did you choose to not put the new batteries in the aft compartment where the Group 24 is located?
2). Have you had the chance to use the system in full action?

2002 250WK #580 Waco, TX

Carl in LA
Captain

Members Avatar

USA
284 Posts

Response Posted - 08/26/2018 : 06:33:52

quote:
Originally posted by Lehooks

Carl, great post. Very well thought out
1) Why did you choose to not put the new batteries in the aft compartment where the Group 24 is located?
2). Have you had the chance to use the system in full action?

We'll see about how well thought out the install is over the years...

1) Batteries are located in the midship holds for ease of maintenance access and adding the weight close to the keel and as low as possible in the boat. The engine battery is still back in the aft hold although it is a sealed lead/acid version.

2) Somewhat... we have been on two three day cruises this summer in in both cases the 200 watts of solar power were enough to replenish the batteries from delivering power to the Norcold chest refrigerator overnight... I will be adding a third 100-watt solar panel as while the system worked during the long sunny days of Southern California summer it's easy to imagine that when clouds gather and stay for a couple of days you'll need the additional generating capacity.

Back on start-up day the MPPT solar controller was able to deliver about 14-amps from the two 100-watt panels and it did that for just long enough to bring the (sort of flat) batteries up... since then - even during recharge in the morning - the charge rate is always below 10-amps even when the Norcold is running.

Also - that contraption of additional aluminum mounting rails has got to go... need to rethink the mounting of the soon-to-be three 100-watt solar panels. One thinking is that it might have been better to go with standard glass and aluminum panes rather than the soft flexible plastic versions... the plastic versions are very light but the rigid panels may have lent themselves to a better mounting system.

Catalina 250 - Pretty Good Boat

Edited by - Carl in LA on 08/26/2018 06:44:21

Lehooks
Deckhand

Members Avatar

USA
11 Posts

Response Posted - 08/26/2018 : 06:50:02

Your Bimini looks different than most I have seen on here. Did it come with the boat or did you add it?

2002 250WK #580 Waco, TX

Carl in LA
Captain

Members Avatar

USA
284 Posts

Response Posted - 08/26/2018 : 07:14:13

quote:
Originally posted by Lehooks

Your Bimini looks different than most I have seen on here. Did it come with the boat or did you add it?

I added the custom bimini... The bimini is tall enough for me to stand underneath and comes fairly close to the back of the boom... I recall I made the rails clear 6'-6" above the deck.

The aft bimini rail is a weirdly bent 1-inch stainless that is clamped to the Catalina aft rail. Academically - it should lay down forward for transport...

In retrospect it would have been better to have known the dimensions of the solar panels and then bent that aft bimini rail another few inches aft... as it is - the plastic solar panel that is located aft of the backstay has to lay over the aft bimini rail - if the aft bimini rail is angled further back the panel could be flat mounted to the bimini fabric and not have the aluminum tube contraption.

I sewed that canvas top and it was a learning experience too (meaning it's good but not a professional fit).

Catalina 250 - Pretty Good Boat

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.