itaia Photometer FM-1, Operating Manual

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Operating manual: PHOTOMETER FM-1 7
regulation light output
A B C D
LED
level condition pin 7 6 5 4 green,red
1 2 3 4
0 B<L1
230 VAC
/ / /
ON
/ / /
1
B>L1;B<L2 /
230 VAC
/ / /
ON
/ /
2 B>L2;B<L3 /
230 VAC 230 VAC
/ /
ON ON
/
3 B>L3;B<L4 / / /
230 VAC
/ / /
ON
Table 2: Indicating LEDs and contactor outputs
Four green LEDs indicate light-level switch combination (no averaging applied) regarding to
current light condition. For example : When light conditions are below the level set for L1,
first LED 1 is lit , when between L1 and L2 second LED 2 is lit, then LED 2 and LED 3 is lit,
etc. Red LEDs indicate the same light conditions and current status of 230 VAC outputs with
averaging applied.
Light levels, output combinations and moving-average interval are software adjustable (refer
to PC software).
2. 4. 2. Use of U/I Analog Outputs
Analogue outputs directly follow current light conditions (no averaging is applied). There are
two outputs for this purpose: voltage (0-10 V) and current (4-20 mA). Simultaneous use of
both is not recommended and can affect accuracy. 230 V AC contactor outputs can be used
at the same time with no affect to accuracy. (For example: tunnel lighting can be switched
on/off by using contactor outputs while light conditions are monitored via analog outputs
connected to SCADA). For distance over 100 metres use of I-current output is preferred. For
brightness calculation use following equations:
B(U)=B
range
*(U-U
dc
range
)/(10- U
dc
range
)
B(U )
= brightness at output voltage U (cd/m
2
)
B
range
= measuring range (100 / 1.000 / 10.000 cd/m
2
) or specified
U = measuring voltage (V)
U
dc
range
= offset voltage for range (U
dc50
= 0,220 V / U
dc500
= 0,028V / U
dc5000
=0,0090 V)
or individual calibration constants
B(I)=B
range
*(I-4-Idc
range
)/(16-Idc
range
)
B(I) = brightness at output current I (cd/m
2
)
B
range
= measuring range (100 / 1.000 / 10.000 cd/m
2
) or specified
I = measuring current (mA)
I dc
range
= offset current derived from offset voltage for range (Udc
range
)
I dc
range
(mA) = 1,6*Udc
range
(V) ; or individual calibration constants