87
Settings
Touch the Edit icon to view or change the settings related to the relay
Target
Enter the desired PPM set point for the product.
Pump Capacity
Enter the maximum flow rate for the metering pump.
Pump Setting
Enter the stroke length setting for the metering pump, in percent.
Specific Gravity
Enter the specific gravity of the product to be added.
Accumulator Volume
Enter the volume of water passing through the water meter to trigger the chemical feed.
Flow Input
Select the flow meter to be used as an input for this control relay.
Flow Input 2
Select the second flow meter, if any, to be used as an input for this control relay.
Cycles Input
Select the virtual input that is programmed as a Ratio calculation of the system
conductivity/makeup conductivity, or select None.
Low Cycles Limit
Enter the lower limit for cycles of concentration, if used. The calculated on-time is
limited to a maximum value if the cycles of concentration gets too low.
Disturbance Input
Select the virtual input or control output that will multiplied by the control setpoint
(Target ppm setpoint). A typical application for this is to use a corrosion sensor as the
disturbance input to adjust the PPM setpoint.
Daily Max Time
Enter the maximum amount of accumulated on-time, in Hand or Auto modes, that the
relay can have between midnight and midnight the next day. If the time is exceeded, the
relay will deactivate, and a Daily Max Timeout alarm will be triggered. The alarm will
clear, and relay allowed to reactivate at midnight the next day.
If the relay was in Hand mode when the alarm was triggered, it will revert to whichever
HOA state it was in prior to being set to Hand.
To override the Daily Max Limit for the rest of the day, press Reset Output
Timeout.
5.3.20
Relay, PPM by Volume Control Mode
ONLY AVAILABLE IF HVAC MODE IS ENABLED. NOT AVAILABLE FOR VIRTUAL OUTPUTS.
Overview
In PPM by Volume control mode, the controller monitors the total volume of flow through up to two analog or
digital flow meters, and after a programmable volume has been accumulated, the relay activates until the calculated
number of pulses from a flow monitoring device to achieve a target PPM level are received.
The user enters the target PPM, the volume of water to trigger the chemical feed, and the data necessary to calculate
the volume of chemical required to maintain the target PPM in that volume of water. The Feed Monitoring device
programming (volume/pulse, assignment of the device to a relay output) is entered in the Feed Monitor digital
input menus.
Volume to Feed (gal or l) = Accumulated Volume (gal or l) x Target PPM
Cycles x Specific Gravity x 106
Volume to Feed (l) = Accumulated Volume (m3) x Target PPM
(Cycles x Specific Gravity x 106) x 1000
Control Operation
As flow accumulates, the controller updates a field called Accumulator Total. When this value is greater than or
