Entel Intrinsically Safe Atex PMR446 Two-Way Transceiver Radio

Entel ATEX PMR446 explosion-proof two-way radio for licence-free communication

The Entel ATEX PMR446 radio supports 8 analogue and 16 digital PMR446 channels, and no radio licence is required for PMR446 versions. DMR digital and analogue operation can be used within the same device, allowing the radios to be configured for both modes. PMR446 versions use a fixed antenna and provide a maximum RF output power of 0.5 W. The enclosure design is specified with protection for explosive gas and dust environments and carries ATEX certification.

What does ATEX certification mean for the Entel explosion-proof radio?

The ATEX marking defines the classification of equipment used in potentially explosive environments. II indicates above-ground operation, 2 indicates a high level of protection, while G refers to gas atmospheres. Ex refers to ATEX-compliant equipment, ib to intrinsically safe protection, and IIC to the applicable gas group. The T4 temperature class indicates a maximum surface temperature of 135 C. The DT900 family carries the ATEX marking II 2G Ex ib IIC T4 Gb, while its declaration of conformity also lists Directive 2014/34/EU.

Analogue and digital PMR446 communication with 0.5 W RF output power

The radios operate in the 446-446.2 MHz PMR446 frequency range. Both analogue and DMR digital operation are available, with 12.5 kHz digital channel spacing. Typical receiver sensitivity is -121 dBm at 12 dB SINAD in analogue mode and -121 dBm at 5 percent BER in digital mode. Audio output power is 1 W, while typical audio distortion is 3 percent. Digital operation uses an AMBE+2 vocoder.

How does Mixed Mode work on Entel ATEX PMR446 radios?

When Mixed Mode is enabled, both analogue and digital transmissions can be received using the same setting, so the user does not need to switch channels between the two operating modes. In addition to digital and analogue operation, individual and group calls are available, while the display-equipped version can also show caller identification. In digital mode, Lone Worker, Man Down and Emergency Button with call interrupt functions can be programmed as options.

Entel ATEX radio with IP68 protection and MIL-STD-810 compliance

The documented immersion test for IP68 protection specifies a depth of 2 metres for 4 hours. The radios are listed as meeting MIL-STD-810 C/D/E/F/G requirements for temperature shock, humidity, shock, vibration, packaging and drop testing. The general operating temperature range is -20 to +55 C, while the storage temperature range is -40 to +85 C. A separate Ta range of -20 to +40 C applies to the ATEX DT9xx marking.

What is the difference between the non-display and OLED display Entel PMR446 radios?

The non-display version uses a minimal user interface and 3 programmable buttons. The OLED display version features a high-contrast screen with white characters on a black background, navigation controls and 5 programmable buttons. The OLED screen can be configured to show simple large-character information or more detailed data. Radio-to-radio cloning is also available on the display version using an optional cable.

Entel PMR446 radio battery life, controls and audio functions

The radios are supplied with an 1800 mAh Li-Ion ATEX battery. In digital mode, the documented operating time is more than 18.5 hours per charge, while charging a fully discharged battery takes approximately 3 hours. Controls include an on/off and volume control, channel selector, PTT button, programmable buttons and LED status indicator. The radio weighs 435 g and measures 138 x 60 x 38 mm with the specified battery, with an operating voltage of 7.4 V.

Noise reduction technology and audio accessory optimisation adjust the audio according to the type of connected audio accessory. The multi-pin accessory connector and Micro-USB socket use a submersible design and gold-plated contacts. The keypad lock is intended to prevent unintended transmission.

Which ATEX accessories can be used with explosion-proof PMR446 radios?

Only accessories approved for use with the radio may be used in ATEX environments. Connected accessories pass through an automatic validation process, while DTEx accessories use a locking connector. Approved accessories include remote speaker microphones, hearing-protection headsets, bone-conduction microphones and earpieces, throat microphones, heavy-duty PTT switches and microphone earpieces. Support for third-party Breathing Apparatus communication kits is also documented.

Licence-free PMR446 use, programming and operation

PMR446 versions can be used without a radio licence. The radio can be configured for digital channels, analogue channels or both operating modes. A PC application can be used to transfer programming data, install software updates and add new functions. The radio must be switched off before charging, a wet radio or battery must not be charged, and only batteries and chargers with the specified ATEX or IECEx approval may be used.

• Advantage: licence-free PMR446 communication in analogue and digital modes.
• Advantage: IP68 protection, ATEX II 2G Ex ib IIC T4 Gb classification and Mixed Mode operation.
• Limitation: PMR446 versions have a maximum RF output power of 0.5 W.
• Limitation: only specified and approved accessories may be used in ATEX environments.

Maintaining ATEX approval also requires defined conditions to be followed during servicing. Repairs and maintenance of the radio may only be carried out by Entel, and damage to the tamper-evident seal invalidates the product approval.

What are the most common questions about Entel ATEX PMR446 radios?

The following questions summarise the technical and operational characteristics most commonly considered when selecting a radio from this category.

• Is a radio licence required?
  No. PMR446 versions in this category can be used without a radio licence.
• Can the radio be used for both analogue and digital communication?
  Yes. The radios support both analogue PMR446 and digital DMR446 operation.
• What does Mixed Mode do?
  When enabled, it allows both analogue and digital transmissions to be received without switching channels.
• What is the IP protection rating?
  IP68, with a documented immersion value of 2 metres for 4 hours.
• Can any headset or microphone be used in an ATEX environment?
  No. Only the specified approved accessories may be used.

When selecting a version, the display requirement, programmable controls, analogue and digital operating modes, and required ATEX audio accessories should be considered together.

Summary for selecting an Entel ATEX PMR446 explosion-proof two-way radio

We recommend first deciding whether you need a non-display or OLED display interface, then determining the required analogue, digital and Mixed Mode functions. For ATEX environments, the approved battery, charger and audio accessories must also be selected as part of the complete system. The common technical basis of the category is the 446-446.2 MHz PMR446 range, maximum 0.5 W RF output power, ATEX II 2G Ex ib IIC T4 Gb classification and IP68 protection.