Centralized placement of instruments and equipment can reflect the professional laboratory style, but also easy to use management, so many laboratories are willing to use this layout, this arrangement is indeed a good choice for some instruments and equipment, but for some large analytical instruments and high-power pre-processing equipment has potential dangers.

1. Easy to produce electromagnetic interference and electromagnetic radiation

For example, the graphite furnace power supply of GFAAS is a low-voltage power supply, which is generally reduced to 12V or 24V by the transformer built into the graphite furnace power supply, and the power can be as high as 4 to 5 kW, which is a large power. The graphite tube is intermittently heated and discontinuous, and the frequent start and stop of the inductive load will inevitably radiate electromagnetic interference and affect the stability of the mains in the quadrant. In addition, the flame AAS supplied by the air compressor is used to ensure the stability of the air supply pressure, and the air compressor is also frequently started and stopped, which will also produce a large intensity of power frequency interference.

As a key component of ICP-AES and ICP-MS, inductively coupled plasma is a high frequency and high power device, which can also produce great electromagnetic interference during excitation. Similar to the above large analytical instruments, their own power consumption is vulnerable to external electromagnetic interference when working, and they may also intermittently leak out strong electromagnetic interference and electromagnetic radiation. If multiple similar instruments work at the same time, it is not only easy to interfere with each other, but also harmful to the health of staff working in this environment for a long time. The design and manufacture of the instrument are in line with national or international norms, and anti-interference safety measures such as grounding shielding have also been taken, even so, it is difficult to completely avoid interference between each other, especially the crosstalk transmitted through the power supply circuit in the same room, so that the analytical instrument has some inexplicable and difficult to explain the performance of the work. It can cause instability of the baseline of instrument analysis, poor reproducibility of analysis and test results, etc. In severe cases, it can cause the instrument to fail to work and cause damage to the instrument.

Suggestion:

Not all similar instruments are suitable for centralized installation in a large instrument room, for those with high power, easy to be electromagnetic interference or easy to produce electromagnetic interference equipment should be considered independent or decentralized placement. The equipment that can be centrally placed should also consider the power supply load capacity of the room. Each laboratory is required to be equipped with a ground terminal box, and the ground resistance must not exceed 1 ohms. An independent grounding wire device is set for each instrument and the grounding resistance value meets the requirements of the instrument manufacturer. Eliminate interference sources to ensure the safe operation of instruments and equipment.

Key details of laboratory layout design: Analysis of advantages and disadvantages of centralized placement of similar instruments and equipment!

Laboratory layout construction SICOLAB

2. Waste electricity and energy

At the same time, let the ambient temperature and humidity of a large space and a small space reach a certain level, and the energy consumption difference of the air conditioning system is obvious. If multiple similar instruments are placed in the same large room, in the case of low instrument utilization, for example, when only one instrument is working, in order to ensure the temperature and humidity of the environment, the air conditioning system will inevitably run with multiple instruments at the same time, resulting in a great waste of power energy, resulting in an increase in inspection costs, which is extremely cost-effective. If the local segmentation method is used, only the independent air conditioning system needs to be opened, and the instrument room that does not work does not need to start the air conditioning system, which is conducive to energy saving and cost control.

Suggestion:

Analytical laboratory instruments are not all working at full load, in order to improve the energy efficiency of environmental equipment and effectively reduce operating costs, the instrument room should be arranged in a relatively reasonable space size.

3. Easy to produce noise pollution

The flame atomic absorption spectrometer using the air compressor to provide constant pressure air, in order to ensure the constant air pressure provided, the air compressor must be frequently started and stopped. Multiple similar instruments work together in the same room, and the noise superimposed when the air compressor works is unbearable. In addition, like ICP-MS, in order to maintain the degree of vacuum when the instrument is working, the vacuum pump must continue to work for a long time, the noise of a single vacuum pump is not small, if two or three such instruments work at the same time, the noise pollution generated by the vacuum pump will be very serious. Inspectors working in such an environment are easy to get upset and tired.

Suggestion:

The instrument room, especially the large instrument room, should be equipped with a buffer room and a special gas cylinder room, and do not place multiple auxiliary equipment with large noise directly in the instrument room, and the gas cylinder room should have an exhaust exhaust system and alarm device, and place fire extinguishing equipment. If there is no separate cylinder room, the cylinder must be put into the cylinder cabinet, and the cylinder cabinet has a pumping system and an alarm device for flammable and toxic gas leakage.

4. Power supply overload, damage low-voltage electrical appliances

For example, multiple ovens and muffle ovens are concentrated in one pretreatment chamber; The multiple electric furnaces and electric heating plates used for pretreatment are placed in a digestion room at the same time, and some are even placed in the same ventilated digestion cabinet;

Placing multiple GFAAS, GCS, and even multiple ICP-AES in the same analysis room... We know that laboratory ovens, Muffle furnaces, multi-electric furnaces, GFAAS, GC, ICP-AES and other physical and chemical inspection equipment are high power consumption equipment, concentrated use is easy to cause room and even floor power load tension. The power distribution construction of our experimental building is configured according to the relevant national norms. Even if the whole building fully considers the requirements of the total load and reserves the safety and development margin, it is difficult for the construction unit to decompose different loads into different rooms, and most of them adopt the load balancing power allocation method. After the installation of such instruments and equipment is used for a period of time, some potential problems will be revealed, such as burning the power socket of the instrument and equipment, burning some of the distribution equipment in the low-voltage distribution box of the corresponding room or floor, and the buried wire and cable in the room and floor work under long-term overload, which may cause heat of the wire and cable in serious cases. The cable was short-circuited and burned, resulting in an accident. When the inspection work is very full, most of the instruments and equipment and similar equipment will inevitably work at full load, which will cause the floor or room power load to increase, when the room or floor power capacity is not enough to supply for a long time, it will inevitably cause insufficient power supply leading to undervoltage power supply, power supply cables and various connection points (piles) on the power circuit heat up. Cause the equipment to work under voltage state. Even if there is a secondary voltage regulator inside the instrument, it will certainly affect the stability of the instrument and equipment, resulting in the reliability and credibility of the instrument analysis data.

Editorial review

Centralized placement of instruments and equipment can reflect the professional laboratory style, but also easy to use management, so many laboratories are willing to use this layout, this arrangement is indeed a good choice for some instruments and equipment, but for some large analytical instruments and high-power pre-processing equipment has potential dangers. For high-power equipment concentrated rooms such as heating rooms and digestion rooms, the load capacity of the power must be fully considered, and sufficient safety margin must be left, if necessary, the power supply cable can be re-laid, and the load should be balanced as far as possible when arranging the layout.