Posted on Leave a comment

Cornelius Carbonator 2000 Teardown

Water Carbonator
Water Carbonator

To run my postmix rig, I needed a carbonator, to turn tap water into soda water. These units are very common in pubs in the UK, and are very simple in construction. The unit is fed water at about 3 bar from the water main & food-grade CO² at about 5 bar from a regulator, and soda water appears at the outlet.

Pump Motor
Pump Motor

To raise the incoming water pressure above the pressure in the carbonator tank, the unit contains this rather large vane pump, with a 230v induction motor for mechanical power. There’s a solenoid valve on the inlet to prevent water flow when the pump is off, and the motor is automatically controlled.

Electrical
Electrical

Above the pump is the electrical wiring & control. This is a simple level control, and reads a conductance probe inserted into top of the carbonator tank, activating the pump when the level in the tank drops below a minimum level, and shutting it down when a max level is reached. There’s also a timeout function, which shuts everything down on lockout if the pump runs longer than a preset time interval as protection in case of such issues as a leak in the system, or dry running without a water feed.

Carbon Vane Pump
Carbon Vane Pump

Coupled to the front of the motor is a carbon vane pump. This type is very commonly seen in food-grade equipment, such as these units, and commercial coffee machines. The unit has a suction strainer, and a built-in pressure relief valve to stop the pipework exploding or the motor from burning out if there’s a blockage in the outlet line.

Carbonator Tank
Carbonator Tank

The final & main part of the unit is this 115mm diameter stainless steel tank, with fittings at the top. This is pressurised with CO², and water is sprayed into it through an orifice. This spray increases the surface area of the incoming water, making it absorb as much of the gas as possible. There’s a pressure relief valve at the top, just in case the internal pressure reaches dangerous levels.

 

Posted on Leave a comment

Clone DCB090 DeWalt USB Battery Adaptor Teardown

DCB090 Clone USB Adaptor
DCB090 Clone USB Adaptor

Since I got my new DeWalt combi drill, I needed a way to charge the batteries without having to resort to sticking blade terminals into the pack connectors – I didn’t purchase the branded charger, mainly due to cost. I also have a very capable multi-chemistry charger that handles multi-cell lithium packs with no issues, so I saw no need to replicate things. This little gadget was ordered just for it’s main pack connector; I can then use this to make up a charger adaptor cable. What this normally does is allow the use of DeWalt XR battery packs to charge mobile devices via 5v USB outputs, so there’s going to be some kind of DC-DC converter in here. There’s also a “charge level indicator” built in, which doesn’t actually do anything sensible – even on a flat battery pack, showing a single LED on it’s charge indicator shows the full 3 LEDs on this unit.
The remaining feature is a trio of white LEDs to function as a torch, but it’s less than stellar in the brightness department. Given that there’s not much in the way of control inside the battery packs themselves, I reckon this unit could actually overdischarge a pack, causing damage.

Torch LED & Charge Indicator
Torch LED & Charge Indicator

The top of the unit has a large label with windows in for the various LEDs, and a pad covering the tactile switch to operate the torch function.

Label
Label

The label on the side indicates the unit will operate down to 10.8v, good for the 3S packs, as well as the 18/20V packs.

Pack Connector
Pack Connector

Here’s what I was after – the battery pack connector. This has the full compliment of pins for all the balance taps too.

Casing Opened
Casing Opened

Removing a label, and a single screw gives access to the internals. There’s not much in here apart from a large PCB, with a few components.

Main PCB
Main PCB

The PCB is pretty sparse. There’s a microcontroller in the top right corner that does the torch LED switching, and the “battery indicator LEDs”. This is completely unmarked, which is very common now for Chinese microcontrollers. The only way I’m identifying this one is via a decap operation on the IC!
The USB ports have MOSFETs in their negative pin paths, probably to switch off the ports if they’re overloaded. The data pins are bridged together on one port, and connected to the DC-DC converter on the other port.

DC-DC Converter
DC-DC Converter

The main DC-DC converter IC is in the bottom right corner of the board, next to the input pins. This is an IP6503S multi-protocol USB charging converter, with a 24W power limit. This explains why the data pins of one of the USB ports is connected back here – it’s doing some communications with the connected device for fast charging. Chinese datasheet below.

Posted on Leave a comment

Yellow Jacket Titan P51-870 Digital Manifold Teardown

Front Panel & LCD
Front Panel & LCD

New tool time! I figured now I’m a fully ticketed member of the F-Gas community, I’d treat myself to passing the course by buying a decent set of refrigeration gauges. This is the Yellow Jacket P51-870 Titan manifold, a fully digital unit with all the useful functions built in. Basically an electronic module attached on the top of the standard Titan manifold, this unit performs all the regular functions I’d normally need either a calculator for, or other tools. The front of the unit has just a power button, LED & a large resistive touch TFT panel for display.

Rear Panel
Rear Panel

The rear panel has the ports for charging the internal battery, which is micro USB – this is also used to download log data to a PC from a system processing run. There are 4 3.5mm jacks for the external temperature probes, and vacuum sensor.

Rear Cover Removed
Rear Cover Removed

Removing 4 Torx screws in the back panel allows the clamshell case to come apart, showing the mainboard, and the pressure transducers screwed into the manifold. The aux jacks & the USB charging & data port are supported on small vertical PCBs plugged into the mainboard via 0.1″ headers.

Main PCB Overview
Main PCB Overview

With the pressure transducers unplugged from their looms to the mainboard, the module is free from the manifold section.

Main Microcontroller
Main Microcontroller

The muscle of the operation here is a Freescale (now NXP) Kinetis K2 Series MK22FN512VLH12 ARM microcontroller. With a Cortex-M4 core at 120MHz, there’s a bit of beef here. The LCD & touch overlay is controlled by a Bridgetek FT810Q Embedded Video Engine. The video controller communicates with the microcontroller via SPI, and the LCD via parallel RGB. There’s some SPI Flash memory up on the left, for log data storage, a Winbond W25Q32JV 32Mbit part. Just under that is a pressure sensor, which I’ve been so far unable to pull a part number off. This is required to assist in calibration of the main pressure transducers.



Switching Section
Switching Section

In the top right corner of the board is a 74HC595 shift register, with quite a few discrete transistors & diodes hanging around it. I suspect this is used to switch between two vacuum sensors when both are plugged in – from looking at the waveforms present on the sensor interface, the power does appear to be switched ON/OFF on a single sensor at about 1Hz.

My guess at the moment is that the sensor communications are over I²C, by the 4-wire connection, and the very obvious clock & data line on the connector, but I haven’t yet looked deeply into this.

Main Power Supplies
Main Power Supplies

Next to the battery connector (the battery itself is a single LiPo pouch cell, double-sided taped to the front shell, behind the display), are a selection of DC-DC converters, providing all the required voltage rails. No doubt there’s lithium charging control going on here too.

Bluetooth Module
Bluetooth Module

Wireless connectivity is provided for by a Silicon Labs Blue Gecko BGM111A256V2 Bluetooth 4.2 SoC module. These are also fairly powerful parts, with a full ARM Cortex M4 microcontroller hiding inside, clocked at 40MHz. There are as a result two programming headers on this board, in the top left corner, for both this part & the main microcontroller.