Friday, May 2, 2014
Product review: Rocketek 3A/15W car charger with 2 USB and 2 car splitter adapter
Can this charger power 4 devices? Yes, with caveats.
This charger allows you to split one car outlet into 4 outputs: two car ports and 2 USB ports. We always have a lot of devices along 2 tablets, 2 phones, sometimes we use a dedicated GPS rather than the tablet for navigation, we also have external speakers and occasionally a cooler. Could this one splitter power 4 devices at once? Yes, although I found some limitations.
I could not charge two tablets (iPad Mini and Galaxy tablet) on the two USB ports at the same time. I could charge one of the tablets and a phone. The two tablet together was drawing too much current, it would only charge one of them, the other one was discharging. However, I could charge two tablets if I put one of them on USB port and another one one of the cigarette lighter ports.
In our car one of the car ports was very close the gear shift, which made it difficult to plug an adapter into it because it interfered with the driver's ability to shift (see video). This will obviously vary from car to car.
Rocketek charger is 3.5" wide, 4.25" long (from ports to the end that goes into the car port), and 1 1/8" thick (the face where the outlets are). It weighs 2.7oz.
Options that did work:
Two two cigarette lighter ports have no electronics, they are just like having an extension cord. So each of them could deliver as much power as the original cigarette lighter.
I was able to put a double USB car charger in middle cigarette light port (the one that did not interfere with the driver) and was able to charge 4 devices at the same time: 2 phones and 2 tablets. The charging of speed of each devices was excellent, at the top of the chargers I have tested.
Android devices (starting with Jelly Bean 4.21) perform as well on port designed for Apple as the ones designed on Android. So Nexus 5 phone, Samsung Nexus phone, and Samsung Galaxy 7.7 performed equally well on both USB slots as well as on the two car ports. iPad mini performed well only on the port designed for Apple. It worked on the port labelled Samsung, but at much slower speed at the protocol on that port was not designed for Apple devices.
Both cigarette lighter ports are rated as DC12-24.
Output voltage is 5V and output current is 3A.
For those who like reading the details of the tests I am including the two sections below.
➨ How I tested this charger and cable
To test this charger and cable I used a current monitor. In addition to the current monitor I also used a 10 minute charging test which is less abstract than the measurements of current and voltage. These tests allow me to compare various chargers and charging cables to each other in unbiased way based just on their performance.
The 10 minutes test consists of charging each mobile device on each port of the battery pack for 10 minutes and measure how much each unit was charge in that 10 minute period. Since the charging speed is non-linear I start charging each device from approximately the same charge level. Each line in the table below represents a separate 10 minute test. I use Battery App by Elvison to determine how each device recognized the charging source. 'AC' status means the charging is at full charging rate. 'USB' status indicates charging at a lower charging rate. 'Discharging' status means that the charging rate is below the power that the device is consuming so it slows down the discharge rate but does not re-charge.
➨ Test Results:
✔ 4 devices together Nexus 5 phone, Nexus Galaxy phone, Galaxy tablet, iPad mini
iPadMini ~~~~~~~~~~~~~~~~~ Apple USB port ~~~~~~~~~~~~~~~~~ 6%
Nexus 5 ~~~~~~~~~~~~~~~~~ Car port + Bolse car charger ~~~ 6%
Samsung Nexus phone ~~~~~~ Samsung USB port ~~~~~~~~~~~~~~~ 10%
Samsung Galaxy tablet ~~~~ Car port + Bolse car charger ~~~ 3%
✔ Devices charged one a time
iPadMini ~~~~~~~~~~~~~~~~~ Apple USB port ~~~~~~~~~~~~~~~~~ 7%
Nexus 5 ~~~~~~~~~~~~~~~~~ Car port + Bolse car charger ~~~ 9%
Samsung Nexus phone ~~~~~~ Samsung USB port ~~~~~~~~~~~~~~~ 9%
Samsung Galaxy tablet ~~~~ Car port + Bolse car charger ~~~ 4%
✔ Current drawn by each of the devices Nexus 5 phone, Nexus Galaxy phone, Galaxy tablet, iPad mini
Samsung Nexus phone draws 1.03A/5.11V on both Apple USB port and Samsung USB port
iPad Mini draws 1.64A/5.07V on the Apple USB port, and 0.93A/5.07 on the Samsung USB port
Nexus 5 draws 0.80A/5.04V on both Apple USB port and Samsung USB port
Samsung Galaxy tablet draws 1.42A/5.10V on both Apple USB port and Samsung USB port
The charger worked well and provided a lot of flexibility for charging multiple devices.
You can find it on Amazon by following this link.
Ali Julia review ★★★★★