GB 5959.6-2008Safety in electro-heat installations -- Part 6: Specifications for safety in industrial microwave heating equipment (English PDF)

3.2 The electrical and mechanical components for the assembly of microwave energy transmitted to the material to be treated, typically includes a power generator, is applied, even

Cables and waveguides, a control circuit, material transfer means and ventilation.

3.5

Microwave heating device loaded material to be treated and the portion exposed to microwave energy.

3.6

The applicator can be opened without tools or relieved, so that access to all the internal structural member applier.

3.7

In addition to the microwave heating device is applied, it can be opened without tools or any Remove all the structural member as a backup inlet.

3.8

Any use of the tools on the microwave heating device to open or remove, providing access node for routine maintenance, replacement of consumables and other services member.

3.9

A permanent opening in the continuous microwave heating device application, a material to be treated by the application is input or output port.

3.10 It refers to the export in addition to internal staff touchable parts

Note: internal or external surfaces of import export believed to be inaccessible.

3.11

Mechanical or electrical safety devices of the microwave heating device or system, whose function is prohibited when an accident does not exist in another state level occur.

Note 1. For example, if the application is not closed the door interlock to prohibit a microwave generator work.

Note 2. For interlocking design, see GB/T 16855.1-2005.

6.1 Microwave leakage limit

6.1.1 Design of the microwave heating device, manufacture and operation of which is effective to prevent radiation generated by the microwave leakage hazard.

The application may be in contact with the parts of the body (see 3.10) and all devices have more than the microwave leakage tolerable risk limits, provided Protective measures such as the installation of the cabinet door or barrier with interlock (see 3.11) a.

In the microwave heating apparatus of "normal operation" state, where the distance from any portion of 0.05m or more at any volatile Near the which leakage of microwave power density should be no greater than 50W/m2 (5m W/cm2); the device is in the "non-functioning" state, then Should not exceed 100W/m2.

In the microwave heating system should be operated in a predetermined manner when 6.3, with 6.2 to meet the requirements of the measuring instrument to determine the maximum microwave leakage Compliance with provisions of this article.

6.1.2 has a barrier to limit the proximity of the art microwave heating device spaced a distance, if the microwave barrier has compliance 6.4.2 Interlock, you can press the provisions of this clause.

6.1.3 This section provides a microwave leakage value distance from any part of the microwave heating device accessibility for the remote measuring 0.05m (meaning Emission values).

Note: GB 10436-1989 makes provision for the maximum amount of microwave radiation operator of radiation.

Microwave leakage measured 6.2 Microwave leakage measurement instrument should meet the following requirements.

a) step of the input signal, the instrument should be achieved within 2s ~ 3s 90% of the actual steady value;

b) having a work only in the vicinity of the non-polarized radiation detector;

c) measuring the operating frequency of the microwave heating apparatus capable of +25%/- measuring 20% (± 1dB) accuracy of 50 W/m2 ~ Power density of 100W/m2 (the plane wave).

6.3 Measurement conditions

6.3.1 Normal operation

It should allow the microwave input power range and variety of materials under working conditions according manufacturer and user of the microwave heating device is measured The maximum microwave leakage from any part of 0.05m or farther at any accessible device.

6.3.1 measurement should be repeated in the case of open or remove all of the cabinet doors, doors and covers of the applicator. However, remove or open this Some, its microwave interlock interrupts the exception of microwave power produced.

It should be adjusted to the most unfavorable position of the microwave power still generated in each interlocked with the microwave cabinet door, door panel or the application situation 6.3.1 measurement was repeated under the conditions.

6.3.2 Non-load running

6.3.3 No-load non-normal operation

Treated material should not be installed in the applicator and the microwave energy generator is adjusted to the maximum power allowed by the device or interlock will not When so that the maximum power of the microwave heating system damage, 6.3.1 and 6.3.2 of repeated measurements.

6.4 Requirements microwave interlock

6.4.1 Application door

The application of microwave heating device door is opened, should be at least two microwave interlock operation, the design of the locking device should have a high Safety and long service life (in line with GB/T 16855.1-2005 second danger level).

When applying mechanical or electrical door interlock device malfunction, an alarm should be issued, while the microwave heating device is stopped.

When any mechanical or electrical component failure, all the microwave door interlock of any application should not be out of action.

Each application should be at least one microwave door interlock device is hidden when the door is in an open application, or any intermediate position, this Interlocking means so that the operation is not possible with any part of the body.

Design of Microwave interlocking means should be such that when the door is opened or closed application, not more than 6.1 microwave leakage predetermined limits.

6.4.2 Cabinet doors and covers

If the cabinet door or cover the microwave heating apparatus is opened or relieved, which microwave leakage exceeds a predetermined value of 6.1, then each cabinet door Or to open or remove the cover should have at least one microwave interlocking action.

To ensure safety, usually it requires two independent interlock with each other.

6.4.3 Microwave absorbing means

Microwave heating device having a microwave energy absorbing device stream, if any absorbent means a reduction in the liquid will flow at the outlet Microwave leakage predetermined value more than 6.1, there should be at least one microwave interlock operation.

Continuous conveyor belt means requires 6.5 pairs Continuous conveyor belt system having a working system should meet the following requirements. If the height is greater than the entrance conveyor 10cm, the filter The length of the region should be at least 50cm (see FIG. 1).

6.7 Other safety devices

Each microwave power supply apparatus to be provided when the appropriate signal is given when the power switch on, the signal for each person entering the zone of the microwave heating apparatus Should be prominently visible.

The microwave power can be controlled by changing the user, there should be an indicator to show the size of the microwave power used.

The power supply control panel should be equipped with safety lock, the key of the microwave power required to produce unlocking.

7.1 Overview

Design, manufacture and operation of microwave heating devices should be considered to minimize burns, risk of fire and explosion. In addition to GB 5959.1-2005 Outside the terms should meet the following requirements. […]

7.2 Fire

The following is possible to provide a microwave heating device, if the material due to overheating may cause fire safety hazards, necessary recommendations Automatic apparatus functions.

a) indicates a fire;

b) in case of fire, cut off the microwave treatment continued to be exported and can be material other forms of energy;

c) in case of fire, the material to be treated to stop the delivery of the applicator; d) fire.

Instructions provided by the manufacturer should be noted that, since the arc may cause a fire if the application is in, it is also to be taken 7.3.2 Precaution.

If the microwave heating device to produce fire-prone work indoors, you should take precautions 7.3.

7.3 Explosion

Instructions provided by the manufacturer should be noted, not in danger of the explosion chamber using microwave heating, generally should not be used at Cause danger of explosion when processing the material is heated. When the microwave heating must be carried out on these materials, the following precautions should be taken.

7.3.1 If the workpiece released from the combustible gas in the heating process is potentially explosive, special precautions should be taken to avoid Free form an explosive atmosphere within the applicator. Suggest.

--- provide sufficient air to the furnace, in order to ensure the air ratio of the combustible gas does not exceed the lower limit of the flammable range of the quarter;

--- providing apparatus can automatically cut off the input microwave power is applied when the exhaust system failure;

--- valve disposed combustible gas explosion that may occur in a microwave oven at a volume of greater than 0.5m3.

7.3.2 should take special precautions to avoid arcing within the applicator. In addition, the description provided by the manufacturer should be used in Emphasize.

--- mating face and clean the inside of the door of the application application;

--- ensure material to be treated is not mixed with foreign bodies can cause arcing, such as metal shavings.

In order to reduce the risk of arcing, the choke recommended application door structure, while the structure without metal to metal contact.

7.4 Ionizing radiation

In the microwave heating apparatus of the outer surface of the measured X-ray leakage of microwave energy from the generator should not exceed the GB 5294-2001 Provisions.

8.1 Launch

Transmitting a radio frequency electromagnetic field comply with the requirements applicable portion GB 4824-2004. If necessary, consider the harmonic current and voltage fluctuation effects.

Note: with rated input current is not greater than the apparatus 16A, GB 17625.1 "electromagnetic compatibility limits for harmonic current emissions (equipment input Flow 16A or less) "and GB 17625.2" electromagnetic compatibility limits of the rated current generating device 16A is not greater than the low-voltage supply system Voltage fluctuations and flicker limit "applies; of greater than 16A is, GB /Z17625.6" electromagnetic compatibility limits of the rated current greater than 16A Limits the harmonic currents generated by the equipment in low-voltage supply systems "and GB /Z17625.3" electromagnetic compatibility limits of the rated current greater than 16A Of voltage fluctuations generated in the power supply system and a low pressure limit flicker "apply. Greater than the rated input current of the device 75A, See IEC 61000-3-11.

NOTE: Immunity Industrial equipment requirements, according to GB/T 17799.2 "General Standard Test EMC immunity to industrial environments." 1 --- conveyor belt;

3 --- cavity.