Sonic Alert Digital Program Controller DCP301 - Manual (Page 120)

Chapter 7. PARAMETER SETUP
7-35
● C 7 8 (voltage output 1 adjustment)
● C 7 q (voltage output 2 adjustment)
When driving an SSR by voltage time-proportional output, the output voltage of the
controller must be within the input rated voltage (optimum ignition voltage) of the SSR.
On the DCP301, a newly developed variable output system is utilized that enables output
of the optimum ignition voltage even when driving two or more SSRs.
This system sets the optimum current value on the controller so that the optimum ignition
voltage with respect to the internal impedance of the SSR side can be obtained.
The following shows equivalent circuits and related formulas.
• Description of Symbols
(1) Details
I
O
: Setting output current of controller (setting range: 2 to 22mA)
V
O
: Maximum applied load voltage (approx. 14.7V)
V
SSR’
: Actual input voltage to SSR
V
SSR
: Input rated voltage range of SSR (V
SSR/MIN
to V
SSR/MAX
)
V
SSR/MIN
: Minimum input rated voltage of SSR
V
SSR/MAX
: Maximum input rated voltage of SSR
Z : Internal impedance of SSR
V
D
: Internal voltage drop of SSR (normally 1 to 2V)
(2) Equivalent circuit when one SSR is connected
DCP301 SSR
+
–
+
–
I O
(V O ) V SSR'
Z
V D
Formulas (1) and (2) formulas must be satisfied.
(1) formula V
SSR/MIN
≤
I
O
x Z + V
D
≤
V
O
(2) formula V
SSR'
< V
SSR/MAX
(V
SSR'
= I
O
x Z + V
D
)