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Anesthesia Machine System

Anesthesia Machine System Main Characteristics

Anesthesia system also known as anesthesia workstation consists of the ‘anesthesia machine’, ventilator and breathing system. Others are scavenging system and monitors. Further to these, you may add drug delivery system, suction machine and data management system.

The anesthesia machine

Anesthesia machines comes in variety of shapes and sizes. Anesthetic machine use and working principles is the same with different machines. However, added features from manufacturers separate between each type. Apart from this, parts may differ by shape and size but still call by the same name. For example, Vapourizer. check vaporizer for Boyle’s anesthetic machine which is different from draeger.

Because of danger of electrostatic discharge, body of anesthetic machine and accessories are produced with anti static material.

Anesthetic Machine Parts

Anesthetic machine parts include but not limited to the following: Rotameters or flow meters, vaporizing bottles also known as vaporizer and oxygen gas. Others are anesthetic vapor, nitrogen supply, carbon dioxide supply and breathing circuit accessories. Further are oxygen flush, cylinder yokes, soda lime canister, sensors  and gas regulators.Anesthesia Machine

The Anesthesia Machine CWM-301C
  • The anesthesia ventilator uses a pneumatically-operated electronic control mode, a 10.1-inch color LCD display that monitors various breathing parameters.
  • It is suitable for the medical department to perform circulatory tightness, semi-closed, semi-open inhalation anesthesia, controlled or assisted breathing, and monitoring and display of patient’s ventilation parameters.
  • High precision evaporator with precise concentration control. Advanced temperature, flow and pressure compensation techniques are used.There are various evaporators such as enflurane, isoflurane, and sevoflurane.
  • The integrated anesthesia breathing system (external respiration circulation circuit) has good sealing performance, convenient operation, beautiful appearance, easy cleaning and disinfection, and can withstand high temperature of 134°C. (According to the needs of users, optional buried sensor integrated anesthesia breathing system and loop heating system).

This machine is just one in our list and feel free to Contact Us for more information or Request a Quote

Solar Powered Outdoor Lights

What an advantage it is to get free lights for your comfort at night? There are many ways to light your corridor at night but not without a cost. The cost of this solar-powered outdoor lights is the initial cost to purchase the item. Then the cost of exposing the solar panel/lantern to sun’s rays during the day.

If you’re not tight on a budget, you could have a central solar system installation for your facility. for more information on that go to  solar panel installation with everything ready-made. However, if you just need to light few bulbs at night then you can choose to buy some of the single standalone unit.

Any solar system consists of solar panel, batteries and battery charger. Others are  charge regulator for fairly large to very large installation, low voltage battery disconnect and of course the load. The load in this case is the bulb.

This product may not require a charge regulator because it use low power. At the same time, it is a complete product. However, you can go smart when you combine the tiny solar panels in parallel like say six for example for more power output.

solar powered outdoor lights

Source: http://www.talkingelectronics.com/projects/SolarLight/SolarLight.html

Solar Powered  Outdoor Lights Design Option

Design method for solar outdoor light varies. A design make use of a single cell (battery) which supply high frequency pulse current to a powerful LED bulb. It has the same result on the LED as a dc supply with the advantage that it uses half of the power. The battery and charger are inside the base/handle of the bulb. You can use any of two options to charge the bulb, either from mains electric grid power or pure sunlight.

In the design for this solar-powered outdoor lights, they make provision for rainy and brighter days. The solar panel has enough solar cells to provide enough charging when sun is not bright.

Anesthetizing Location PM for non flammable

Definitions of Anesthetizing Location What is an anesthetizing location? An anesthetizing location is an area of the hospital. This area assigned by the hospital for the normal administration of an inhalation anesthetic agent. And in most cases, this refers only to operating rooms and delivery rooms. What is the meaning of non flammable location? As the…

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Dimmer Switch Unit vs Regular Switch?

Dimmer switch Unit vs Regular Switch?

You can turn on any lights be it at home, in a machine, or vehicle by using the ‘regular switch’ but sometimes for some reasons you don’t want the full beam of light therefore, you use the dimmer switch unit so you can go from high beam to low beam and vice versa. Regular switch simply provide two switching levels ON or OFF.

Sometimes the arrangement is three positions, that is, high, low and off. However some applications demand smooth control of light intensity between low and high. In this case intensity is continuously variable using any of different variations and technique used for dimmer. There are different Variations of Dimmer Switch including:

  1. Programmable control via ARDUINO etc.
  2. Some phase shift control by TRIAC
  3. PWM power control
  4. Simple transistor control
  5. Steps Transformer Control
  6. Potentiometer/Rheostat
Where is a dimmer switch useful?

A dimmer is actually power control device. It will work with incandescent and LED lights, and DC motors; also heating elements such as power control of heating devices like heating element in Water Bath, Incubator, and hot air oven/sterilizers. However there are design variations and degree of complexities. Simple dimmer do not give smooth control but it does work. One good thing about this is that it is durable and sustainable. Precision not seriously but it is accurate.

Dimmer Switch is used in:

  • Light intensity control for ophthalmic equipment like microscope: ophthalmoscope, slit lamp, bipolar coagulation diathermy etc.
  • Light intensity control for homes and apartment
  • Could be adapted to speed control of small electric motors
  • Oven control
Dimmer switch unit
auto transformer power control
How do I make a simple Dimmer switch?

The simplest dimmer switch is a variable resistor also commonly called rheostat. However, rheostat wastes lot of power as heat, hence it is good where power loss is not important. You achieve control by varying the resistance between the light and the power supplies. When using variable resistor in a circuit to vary brightness of a light bulb, you make the resistance greater when you want a dimming experience.

At the same time, you make the resistance smaller when you want a brighter light setting. You increase resistance by increasing the length of the path of resistive material through which the electrons have to flow. Meanwhile, you decrease resistance by decreasing the length of the path.

Solenoid Water Control Valve

What is a solenoid water control valve?

A solenoid water control valve is an electromagnetic device. It function to open or close access to water flow. We can use to open or close access to any fluid such as a gas or oil etc.  The video below demonstrates different component within a typical solenoid valve.

(1) Inside a cheap ebay solenoid water valve  from YouTube

Any current carrying coil will produce a magnetic field. This exert a mechanical force of attraction or repulsion on any magnetic object. It produce the same effect like a permanent magnet. However, in this  case it is an electromagnet because it become a magnet through a current carrying coil. That is, the field could be made to turn ON or OFF as desired by switching the current through the coil ON or OFF signal. This magnetic effect find applications in magnetic relay, solenoid and some other types of transducers.

What is a solenoid valve?

A solenoid is a device that produces mechanical motion when a current carrying conductor coil receives electric current. The movable portion of a solenoid is the armature. A relay is a solenoid set up to activate switch contacts. This occur when its coil receives electric current. The minimum amount of coil current to actuate a solenoid or or relay from its “normal” (de-energized) position is Pull-In current. Drop-out current is the maximum coil current below which an energized relay will return to its “normal” state. See how a solenoid valve works.solenoid water control valve

Armature is the movable magnetic object, and you can move most armatures with either direct current (DC) or alternating current (AC) energizing the coil. The polarity of the magnetic field is not important for the purpose of attracting an armature. Therefore. you can use solenoids to open door latches by electrical means, open or shut valves, move robotic limbs, and even actuate electric switch mechanisms. Like a relay, a solenoid valve may be normally open or normally closed.

However, signal to energize the solenoid valve could come from a remote switch or another transducer. This may be light sensing, heat sensing or pressure. Others are magnetic sensing, or whatever we desire as our signal source.

Soldering How to Guide

How to Solder Soldering how to guide focuses on soldering for beginners and how to solder different components using different methods. This information care for the experienced as much as newbies. At first soldering can seem discouraging, when you give it a try, you will find it easy and simple in most applications. Like everything…

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Anesthetic Machine Failure

Anesthetic Machine Uses

A continuous flow anesthetic machine is most commonly used in advanced  countries of the world. Although its used in many developing countries too.  Its purpose is to deliver accurate and continuous supply of oxygen, nitrous and any other medical gases. In the flow, the oxygen mixes with accurate concentrated anesthetic vapor such as halothane or isoflurane. Further, the mixture is delivering to the patient at a reduced and save pressure through gas regulators and flow meters. However, some anesthetic machine includes ventilator, suction, and patient monitors.

Anesthetic machine failure

Best Anesthetic Machine

It’s nice buying new machine which is affordable compared to used ones. Sometimes, refurbished are not proper and you are unsure of its status. Especially for life saving device like anesthetic machines. Anesthetic machines and ventilator just like other medical equipment are sensitive. Therefore, requires standards especially the vaporizer, rotameter also known as flow meter.

Components which causes anesthetic machine failure include the gas regulators/and gauges requires competent personnel to carry out proper standard tests and calibration. This at most obviously out of reach in most developing countries. You need equipment sources with warranty and maintenance plan. Be it new or refurbished equipment, the margin in price are usually very small. I always recommend new equipment to my clients. You can choose between branded and generic machine and each of them have merits and demerits. Do you need good quality anesthetic machine with ventilator and patent monitor backed with technical and users level training? Contact us for more information.

Anesthetic Machine Failure

Anesthetic machine failure include leakages which are the most common problem with all appliances using air and gas and anesthetic machines and Ventilator are no exceptions. These happen through the joints, and fittings; also through the gas pressure reducing valve (regulators) or the flow meters and this is usually as a result of aged O –rings, ruptured rubber, corrugated tubing and host of many others. However it is imperative to test and confirm there is no leakage of gas be it nitrous, oxygen, air and the anesthetic vapors.

Precautions Handling Anesthetic Equipment
  1. Ensure NO OIL or Grease to avoid fire or explosion
  2. Tight-to-tight! Do not over-tight screws, bolts and nuts to avoid breakage because tubing, piping, nuts and screws are essentially copper and or brass materials.
  3. Use threading tapes for tight fit
  4. Ensure Anesthetic and Operating Rooms floor contains  anti-static rubber materials. Anti Static floor tiles prevents static buildup in the presence of anesthetic vapours.

For more information about medical equipment and (OEM) Original Equipment Manufacturers training, kindly make a request through our Facebook page messenger to us. Include your Email address in your post please. Or you may want to contact us. Meanwhile look forward to our new book ‘The Insiders Guide to Basic Medical Equipment Repairs.”

Electronic Symbol and Components

Who Really Uses Electronic Symbol and Components?

Design Engineers, electrical and electronic technicians and craftsmen all use electronic symbol and components. They use them at one time or the other. The engineer use them as materials for his/her design work. Meanwhile, in time of electrical installation, fabrication, or troubleshooting, all the professionals make use of them.

Electronic circuit symbols are symbolic representation of electrical and electronic components in a circuit or schematic diagram. Combination of components in a circuit and how they relate to each other determines how the circuit function. Meanwhile, position of a component symbols be it parallel or series with others determines its function. However, if you know how, you can fashion out a wiring diagram from circuit and vice versa.

Printed Circuit Board (PCB) and wiring installation is a product of circuits/schematic diagram.

How to read and interpret a schematic diagram

To read a circuit, you begin to trace from the left side of the board. But you need to identify power source and switch from other components and how they interconnect. Reading and translating wiring diagram is a skill in troubleshooting. However, if you can read, understand and interpret a diagram, you can easily identify and isolate problem areas in equipment and appliances.

To acquire the skill is not difficult, all you need to do is to identify each component, know all about each component, understand how one component relates to the other. Meanwhile, understand basic parallel connection, series connection and series-parallel circuit theory.  Listed below are examples electrical electronic components symbols.

Example electronic components and symbols listed are Transformer, Headphone, diodes, transistor, resistor and lots more.

Click on any of the Symbols for expanded view.
electronic symbols typical

For an exercise, get a simple circuit online. Identify the components in the circuit. Then, explain how the circuit works. Finally you can post the circuit and your explanation in the comment, or send as a feedback

Medical Suction Machine Fails! What to do?

medical suction machine Medical suction machine is one of the must check before starting a case. An anesthesiologist think through and its of interest to run through a quick checklist of machine; monitors; suction ; airways; IV; drugs etc. to ensure all needed stuffs are intact. There is a necessity to check all equipment and accessories especially the monitor; the anesthetic machine; and the suction apparatus. Notwithstanding, the user checked the items for availability. A Biomedical Equipment Technician need to ascertain all equipment are in good order to function.

Equipment Checklist Before a Procedure

Check the monitors for appropriate probes and secure sensors in place. Sensors are prone to damage through rough handling so its important to keep spare to avoid disappointment, inconveniences and embarrassment. Suction machine on its part are prone to fail due to leakages. The leakages come through cracked and worn-out rubber gasket. This occur at the edge of the lid for the reservoir bottle or from leaks at the joints between the patient nozzle and the reservoir. Similarly, between the plastic tubing and the catheter.

When you have checked the bottle is well covered and well sealed, the gasket rubber may be worn. Similarly if you have a trusty patient plastic nozzle, yet the machine do not come up with usable suction pressure, then, you may need to check the pressure control knob if it’s opened. However, if this is o.k. then, you need to get inside the machine itself. However, someone with technical knowledge is suitable for this tasks because a novice may leave the machine worst than he/she found it.

Problems with Medical Suction Machine

However, do not dismay if you are just starting out but you have some basic technical knowledge, you can confidently open the machine to check little error such as disconnected tubing but if the problem is more than that supervision in the workshop by more experienced technician is necessary. Meanwhile, you can learn more about suction devices

The problem with the machine is probably caused by a leaky capacitor, or open fuse etc. or faulty electric motor especially if fluids managed to escape the cut-off-safety valve into the pump. After you the repair is complete and the machine is now sucking, for safety sake, carry out electrical safety test and do pressure calibration. You need to check the negative pressure with pressure meter and ensure it tally with reading on the gauge. To walk through necessary steps and to receive  updates information and support on medical suction machine and general medical equipment repair and management series, you can Subscribe to Our Mailing List and Newsletter or give your comment below.

 

 

Transistor Switch Design

Precautions Switching Inductive Loads

Many times we need to switch inductive load like solenoid valve through a transistor switch. In fact, some tasks require powering a heavy load via a relay or a contactor. The solenoid valve, relay or contactor and any device with coil primarily acts as an inductor. This is because it’s a coil and the inductors do not like sudden changes in current.

Watch this video for thorough understanding.

Source: Ben Krasnow

However, if you interrupts the current flowing through a coil suddenly, for instance when you open the switch. The coil will react with a sudden very large voltage across its leads. Thus causing a large surge of current through it due to collapsing magnetic field, within the coil as the current is interrupts abruptly. Surges in current resulting from inductive spike can results in thousands of voltage. The inductive spike will possibly harm neighboring devices within the circuit such as switches, transistors and relay contacts etc.

Transistor Switch Circuit

In the transistor switch circuit, a way out of inductive spike is to use what is known as transient suppressors. The suppressor interrupts the current through the coil. Typical transient suppressor is a diode across the relay coil in the relay driver shown below.

Fig 1Fig 1 Relay Driver

The circuit above is a typical transistor switch control driven by an input voltage. When sufficiently large voltage and input current applies to transistor’s base lead, the transistor’s collector-to-emitter channel opens. Thus allowing current to flow through the relay coil. Take note of the diode across the relay coil to eliminate imminent damage to the transistor by voltage spike through the switching of the coil.

Sometimes they use an RC network as a transient suppressor especially for relay using ac. But it’s important to use a resistor and capacitor with rating for a potentially large transient current suitable to the coil current.

In the AC Driven Coil with RC transient suppressor shown above, the capacitor absorbs excessive charge. Then the resistor helps control the discharge to safe limit. A typical RC network for small loads driven from the power line uses 100 Ω Resistor and 0.05 µF Capacitor.

Transistor switch snubber
RC Snubber Circuit from Wikipedia.