FLAME SCANNER VIEWING HEAD FOR FLAME MONITOR
MODELS S550B, S552B and S556B

The IRIS Models S550B, S552B and the S556B Viewing Heads are similar in operation and specifications to the S55x family of Viewing Heads. The two main differences are:

1. The S550B and the S552B have an analog signal output capability.
2. A numeric digital display is provided at the rear of the viewing head to monitor the UV and IR count rates.

For the S550B, the UV count rate is displayed in GREEN on the upper readout, whilst the IR is displayed in RED on the lower readout.

The S550B (shown above and right)) works with the latest version of the P520/P522/P531 and P532 signal processors. Like other viewing heads in the S55x family of viewing heads, the S550B produces output pulse rates proportional to the flame signal strength; the pulse rates are displayed at the front panel of the signal processors. Unlike the other members of the S55x family of viewing heads, certain parameters in the S550B viewing head can be selected or adjusted remotely from the front panel of the P520/P522/P532 signal processors. These parameters are:

• UV gain 0-99

•  IR gain 0-699

• Filter Selection 1-8

Once adjusted, the new parameters are stored in EEPROM in the signal processor. If power is removed from the signal processor (which powers the viewing head) and reapplied, the signal processor then automatically re-sends the stored parameters out to the S550B viewing head. In addition, at the front panel of the signal processor the operator may also select "CAL", a semiautomatic mode which will help to speed up the S550B setup. Thus, the S550B is a dual-sensor viewing head where the gain and filter selections are adjusted and stored remotely by the P520, P522, P531 and P532 signal processors.

The S552B is for IR sensing only. It is basically an S550B without UV capability. The P520, P522, P531or P532 signal processor will be aware of which viewing head of the S55xB family is connected to it so that only those adjustments which are appropriate to the S552B will be made available to the operator. These adjustments apply to the S552B:

• Filter Selection 1-8

• IR gain 0-699

When it comes to features like "CAL", the operator is given only those choices which are appropriate. For example, the operator does not have to choose between calibrating with the UV sensor or the IR sensor; in "CAL" but is only offered the choice of calibrating with the IR sensor.

The S556B is for UV sensing only. It is basically an S550B without IR capability. The P520, P522, P531 or P532 signal processor will be aware of which viewing head of the S55xB family is connected to it so that only the adjustment which is appropriate to the S556B will be made available to the operator:

• UV gain 0-99

When it comes to features like "CAL", the operator is only given those choices which are appropriate. For example, the operator does not have to choose between calibrating with the UV sensor or the IR sensor; in "CAL" but is only offered the choice of calibrating with the UV sensor or not.