YSI DIQ/S 182 XT-4-PR - Manual (Page 19)

System 182 XT-4 Installation
3 - 5 ba76027e01 02/2012
Allowing for the relative
on-time in valves
Valves usually switch on periodically for a limited time and then require
the nominal power. Crucial for the load on the power unit of the DIQ/
S 182 XT-4-PR is the time averaged (effective) power requirement that
depends on the relative on-time, ED:
Relative on-time ED = t
On
/ (t
On
+ t
Off
)
The effective power requirement is the product of the nominal power of
the valve component and the relative on-time:
P = P
nominal
* ED
Since ED is always < 1, the effective power requirement is always
smaller than the nominal power of the valve component.
Note
For the control of sensor cleaning systems operated by compressed
air, a relative on-time of max. 0.1 has been adopted in practice.
Determining the number
of MIQ power supply
modules
From the value determined for the power requirement, determine the
number of the MIQ power supply modules as follows:
Calculation example:
Result: Total power requirement P
<
4.5 W, hence no additional power
supply module is required.
Total power requirement P Number of additional
MIQ power supply modules
P
≤
4.5 W 0
P
>
4.5 W 1
Example configuration 1 Power
requirement [W]
(component)
Total power
requirement P [W] (sum
of the components)
+ 1 VisoTurb
®
700 IQ 1.5 1.5
+ 1 ViSolid
®
700 IQ + 1.5 3.0
+ 1 FDO
®
700 IQ + 0.7 3.7
+ VARiON
® Plus
700 IQ + 0.2 3.9
+ 1 DIQ/CHV (ED = 0.1) (0.8 x 0.1 =) 0.08 3.98
+ 1 DIQ/CHV (ED = 0.05) (0.8 x 0.05 =) 0.04 4.02