Brahma 37106240 CM31F control box

The Brahma CM31F 37106240 controllers are an effective means of controlling atmospheric gas burners with a fan, capable of functioning independently of the presence of combustion in the circuit. They can be equipped with non-volatile or volatile locking. In the case of a non-volatile lock, manual intervention is required to restart after an emergency lock, while a volatile lock restores the operation of the controller through a power interruption.

The CM31F 37106240 control box are used in a variety of devices such as steam convectors, heating boilers, warm air generators, radiator tubular heaters and water heaters. Their flame detection mechanism uses the principle of ionization, however, it is important to note that this mechanism does not have a protective resistance, which makes contact with the detection electrode unsafe.

Features

• Manual reset

• Single flame

• Atmospheric with a fan

Complies with EN298:1993

• Complies with EN298:2003 (2)

• Flame control based on the rectifying properties of the flame (ionization);

• Two independent safety contacts in series at the outlet of the gas valve (models with manual reset);

• Service life of electrical equipment at max. declared load > 250,000 operations;

• Built-in fully solid-state ignition device with high efficiency;

• EU certification type (CE PIN code 0694BR1154) in accordance with Directive 90/396 on gas appliances and the following amendment to Directive 93/68;

• In accordance with EN 298 (European standard for automatic programming and flame control systems for gas burners);

• Auxiliary contact for low-power ignition or control of the main gas valve in intermittent power control systems (this contact is not isolated from the main supply voltage by reinforced insulation, therefore the relay contact is not suitable for controlling SELV circuits

Technical specifications

Power supply: 230 V – 50/60 Hz; on request: 110-120 V – 50/60 Hz

Operating temperature range: -20 °C +60 °C

Humidity: max. 95 % at 40 °C

Degree of protection: IP00

Pre-ventilation time (tv/tp): 20 sec

Safety time (ts): 10 sec

Standby Time (tw): 20 sec

Response time in case of flame failure: ≤ 1 s

Minimum ionization current: 1.2 µA

On request: 0.5 µA

Recommended ionization current: 3-5 times the minimum ionization current

Maximum cable length: 1m

Maximum parasitic electrode capacitance: ≤ 1 NF

Maximum short-circuit current: < 200mA AC

Maximum ionization current (230 V 50 Hz): 8 µA DC

Ignition voltage: 20 kV at 30 pF load

Spark repetition rate: 25 Hz

Maximum cable length: 2 m

Recommended discharge distance: 2-4mm

Power consumption: 2.5 VA

Spark energy: 15 MJ

Weight: 170 g

Construction

The CM31F 37106240 relay provides durable protection against mechanical damage, such as impacts and impacts, thanks to a plastic housing and self-extinguishing material. The case is effectively protected from external factors, including dust and dirt, which contributes to the durability and reliability of the device. Designed with safety and durability in mind, this enclosure aims to minimize the risks associated with exposure from the external environment. To optimize the dimensions of the printed circuit board, a module with electronic components placed on the surface was used. This led not only to a reduction in the size of the device, but also to an increase in its efficiency.

The principle of operation

When turned on, the controller performs self-monitoring of all its components. During the pre-purge or standby (TW) period, the internal circuit of the controller checks the operation of the flame signal amplifier and is blocked if a parasitic flame signal or an amplifier malfunction is detected. In models with fan control, before pre-purging, the controller checks the contact status of the air pressure switch, activates the fan only when the test is successful, and starts pre-purging when the pressure switch is switched to the “air flow” position. After the waiting time or pre-purge has expired, power is supplied to the gas valve, and the ignition device starts the safety time (TS). If a flame is detected within a safe time, the ignition device is blocked. In models with the corresponding function, an independent auxiliary contact is switched, indicating flame detection. If there is no flame after the safe time has elapsed, the controller switches to lock mode, turning off the gas valve and the ignition device.