CONNECTORS CONNECTION by Jef Raskin
|
[Editor’s note: With the right connectors, you’ll have a lighter and more
efficient power system. Given the
variety of available connectors and new ones coming to market, some say it’s not whether you will swap out your connectors on this or that model, but when. This overview will help you make the right choices in selecting connectors that are best for your needs. Weigh the author’s advice on the most important attributes of connectors and pick
the style of connector whose look,
performance and “feel” appeals to you the most.
Weights are provided for connector pins and cases minimally required to connect two wires to two wires (e.g. plugging a battery into a speed control would require 2 dual-pin connectors or 4 single-pin connectors). Maximum current ratings are based on manufacturer recommendations for sport
electric airplanes (e.g., 7.4 to 24-volt systems), and are not intended to characterize upper current limits in
specialized, high-performance systems.] |
| |
TYPES AND TIPS
Encased connector pins:
Astro Flight Zero Loss, Power Poles, Hobby Lobby “Gold Stecker” bullet connectors, Tamiya connectors, “JST”-style micro connectors, and RTF airplane plugs of Chinese
manufacture
Pins with solder pots:
Astro Flight Zero Loss, Power Poles, Hobby Lobby “gold bullets” and “Gold Steckers”
Easiest plugging/unplugging: All brands of micro plugs
Astro Flight Zero Loss, Power Poles, Hobby Lobby “Gold Steckers”
Highest current: Deans Ultras, Astro Flight Zero Loss, Hobby Lobby “Gold Steckers” and “gold bullets,” Power Poles
Tiniest: Hobby Lobby Ultra Light Micro Connectors (less than half the weight of “JST”-style, exquisite engineering), “JST”-style connectors
Easiest to rework/reuse: Deans |
| ASTRO/DEANS 3-PIN MICRO. Deans 3-pin micro connectors, available from Astro Flight, are ideally suited to small brushless motor installations. Pins are gold plated; cases have ridges to facilitate plugging and unplugging. Weight (pair): 1g; Current Max: 7.5 amps; Part No.520; Price—$2 (pair). |
|
 |
ASTRO ZERO LOSS 2-PIN
Astro Flight 2-pin Zero Loss connectors are a “gold standard” in the industry. Gold-plated pins and sockets are completely enclosed in the connector housing. They handle up to 13-gage wire and have less resistance than an equivalent length of wire. The connector at the upper right, attached to small-gage wire, is part of a patch cord that will connect an Astro charger to smaller batteries with small connectors. Weight (pair): 8g; Current Max: 50 amps continuous, 75 amps for two minutes; Part No.525; Price—$ 5.95 (pair)
|
|
 ith electric-powered models we have to get the battery, the receiver, the motor controller, and the motor connected electrically. We could just solder them all together, but that’s slow and limits flexibility. The better solution is to use electrical connectors.
But which ones are best? Will any connector work? We are all familiar with connectors. We use them every time we plug in an appliance, but the connectors we use around the home are too big and heavy for use in model planes. Instead, we use many smaller connectors from the electronics industry or that are specially developed for us.
More and more frequently, systems come completely wired, which means that you have to neither choose nor attach connectors. But when you need to make up a new battery pack, adapt a new speed controller to your existing equipment, or replace a worn unit, you may find yourself choosing connectors.
THE RIGHT CONNECTORS FOR YOU
What makes a particular connector right for you? Here are some important points that you might want to consider.
—Size: Will it fit in your model?
—Weight: Is it too heavy for your model?
—Number of contacts: Servos require three wires, brushed motors two, brushless motors three, and so on. The connector you choose has to have at least as many contacts (sometimes called “pins”) that you need.
—Connection force: Is it so tight that you risk damaging the model in pulling it apart, or will you have trouble making the connection inside your model? Is it so loose that it might come apart in the air?
—Polarization: Can you accidentally plug it in the wrong way, perhaps ruining components?
—Safety: Can it accidentally cause a short-circuit if its pins touch something?
—Current capacity: How much current can it safely carry. Current is measured in amps (A) or thousandths of an amp (milliamps or mA).
—Compatibility: Is it compatible with friends’ setups or club standards (it’s often nice to be able to lend or borrow a battery pack.)
—Ease of attaching wires: Some connectors are easy to wire up, others require more skill and time.
—Availability: A great connector that you can’t find isn’t much help.
—Durability: Will it fail after a few dozen flights or is it good for as long as you fly the model (this can be decades)?
—Mechanical strength: Is the connector likely to break in normal use?
—Special features: Is the connector designed to be mounted on the model so that you don’t have to get inside to connect to it? Can you stack them to make custom arrangements?
—Price. Let’s look at each of these considerations in more detail.
Size. Always consider how long the pair of connectors will be after they are mated. Make sure that you have room for the pair, and that you can get to them.
Weight. For the smallest models–those weighing under about three ounces (85 grams)–a connector that weighs 7.5 grams (0.26 oz.) is a significant portion of the payload. The Astro Zero Loss connector pair weighs that much. It is one of the best products on the market for large models but it was not designed for and it is not appropriate for a really small model. On the other hand, a Deans connector, also gold-plated and of high quality, weighs a barely noticable 0.6 g (0.02 oz.) — and the various JST (aka GWS-style) connectors are even lighter. Remember that wire itself is relatively heavy, being made of metal. Keep your wiring short and direct, but not taut because that puts a strain on the wire and connections that can cause failure.
Page 2 (of 2)
|
On the right is an optional tool that assists in placement of pins in the connector housings as well as their removal. Weight (two pair): 6.8 g; Current Max: 60 amps; Part No. LXD175; price—$ 3.50 (2 pair)