Brahma 37201251 MPI22 control box

The Brahma MPI22 37201251 control unit is part of a series of microcontroller devices designed to control forced-draft burners running on mixed oil and gas fuels. MPI22, as a new product, has the ability to perform all standard burner functions and includes a valve check program activated on request. The convenience lies in the fact that one control unit is enough for this device instead of two, which is a technical and economic advantage. Non-volatile locking ensures the safety of the system, and restart is possible only after manual reset of the control.

A special feature is also the ability to control various types of air dampers, ensuring the versatility of the control unit to comply with the operating cycle in accordance with the current standard. This controller is suitable for controlling a variety of burners, including multi-stage or modulating burners used in domestic and industrial heating systems.

General characteristics

The main features of the Brahma MPI22 37201251 gas control unit are as follows:

− Easy to install and connect;

− the possibility of multiple ignition attempts depending on the final application;

− operating cycles compatible with the LFL1 type controller (Siemens). When replacing the control unit, the outlet should also be replaced;

− flame control due to the flame straightening (ionization) property or using UV1 type ultraviolet phototubes (technical specifications are given in the relevant technical data sheets);

− two independent safety contacts for controlling the gas valve;

− the service life of electrical equipment is max. declared load >250,000 operations;

− built-in and/or remote manual reset with liquid crystal indication of the reasons leading to an emergency shutdown;

− the ability to control the valve inspection system at the pre-purge stage or after purging.

Technical specifications

Power supply: 230 V (+10%/-15%) – 50/ 60 Hz; on request: 110/120 V (+10%/-15%) – 50/ 60 Hz

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

Ambient humidity: no more than 95%

Degree of protection: IP40

Classification codes:

according to EN 298:03 FBLLXN

according to EN 230:05 FTLLXN ”WLE”

Power consumption at startup: 7.5 VA

Power consumption during operation: 9 VA

Weight: 0.95 kg

Dimensions: 10.3×10.3×9.1 cm

Construction

The use of special manufacturing technology and the introduction of SMT technology have made it possible to obtain an extremely flexible device that can control the air flap. The plastic housing protects the control panel from any damage resulting from accidents, careless handling, dust and dirt ingress. The varistor protects the control panel from power surges in the network. A built-in fuse protects the internal control relays in the event of a short circuit at the outputs (gas valves, motor, transformer and lock signal). Since this is not an emergency fuse available, the control unit must be protected by an external high-speed fuse suitable for connected loads and not exceeding 6.3A.

Operating mode

When the thermostats R, W and GP are closed, the device initiates the start of the first burner (M1) with a delay of t7, followed by the start of the second burner (M2). After the t16 delay, the command opens the air flap to the maximum air flow. If the APS air pressure switch is not activated during time t10, the system is blocked. The pre-purge time (t1) precedes the closing phase of the air flap to the minimum air flow. Pre-ignition (t3) then begins, where the ignition transformer is activated. If the control unit detects a flame signal, a safe time t2 occurs. At the end of the safe time, the system checks the flame signal; in the absence of a signal, the system is blocked. The second valve is switched on with a delay of t4 after the first, provided there is a flame signal. The start-up is completed after the delay t5 expires, when the air flap is adjusted between the minimum and maximum air flow using the LR control. At start-up, the position of the air flap is checked, and the control system guarantees its open position before starting pre-ignition. After the ignition sequence, the system commands the modulation to an external LR device.

Patent/certification

− EC type certification (PIN code 0694BQ0913) in accordance with the Gas Appliance Directives 90/396 and 93/68;

− in accordance with the following standards:

− EN 298:03 (European standard for automatic ignition of gas burners and flame control systems);

− EN 676:03 (European standard for automatic forced-draft gas burners);

− EN 1643:00 (European standard for valve inspection systems);

− EN 267:99 (Forced draft oil burners);

− EN 746-1:97 (Industrial heat treatment equipment);

− EN 746-2:97 (Industrial heat treatment equipment);

− EN 230:05 (European standard for automatic flame control systems for oil burners).