Limit 1 & limit 2, Rt-30ex flow transmitter – AW Gear Meters RT-30EX User Manual
Page 25

RT-30EX Flow Transmitter
Operation and Programming Manual
25
RT-30EX User Manual, Rev. 1.7 02/07/2012
Limit 1 & Limit 2
Turn Limits OFF
To turn either of the Limits off, choose the OFF Limit Type and press
ENT
. The corresponding Limit pin
will now stay low regardless of any variable changes.
Frequency Output on Limit pins
To have the incoming frequency be routed to a Limit pin, choose the Frequency option. There is no
other programming required.
Cycle Output (pulsed output)
The CYCLE OUT limit function provides an incremental output signal for a remote totalizer, typically at a
lower resolution and frequency. Assigning a limit to the CYCLE OUT function toggles the state of the
limit output whenever the TOTAL increments by the programmed cycle amount. The output remains ON
until the cycle amount accumulates and does not turn OFF until the cycle amount accumulates again as
represented in Figure 31 on page 26. The total accumulated between a rising and falling edge is the
cycle value. The total accumulated between any two rising edges is twice the cycle value. You enter the
cycle value in programmed engineering total units.
Do not program a cycle amount that produces more than 20 pulses per second (20 Hz).
Consider the maximum flow rate to determine the resulting output frequency. The frequency produced
(in Hz) is the actual flow rate in Engineering Units per Minute divided by 120, divided by the CYCLE
AMOUNT.
Select Limit
Limit 1
Select Limit type
> _____________
~OFF
~Frequency
~Cycle Output
~Limit
UP/DN
ENT
Scaling menu
Limit 1 & 2
Source options
Caution
Enter cycle volume
00000.00 GPM
ENT
Figure 29: Limit 1 & Limit 2 output options
Figure 30: Cycle Output volume scaling