Specifications

Transmitter O

M300 45

M300

Printed in Switzerland 52 121 305

10.3 Mode

(PATH: MENU/PID Setup/Mode

This menu contains the selection of control modes using relays or analog outputs. Press

[ENTER].

This menu assigns a relay or analog output for PID control action as well as details of their

operation. Based on the control device being used, select one of the following three paragraphs

for use with solenoid valve, pulse input metering pump or analog control.

Pulse Length – If using a solenoid valve, select "Relays" and "PL", Pulse Length. Choose the

ﬁrst relay position as #1 if the Reverse control action is needed. Choose the second relay

position as #2 for Direct acting control. Set the pulse length (feed cycle time) in seconds. A

short pulse length will provide more uniform feed. A longer pulse length will reduce wear on the

solenoid valve. A value of 30 seconds may be a good starting point. The % "on" time in the

cycle is proportional to the control output.

Pulse Frequency – If using a pulse input metering pump, select "Relays" and "PF", Pulse

Frequency. Choose the ﬁrst relay position as #3 if Reverse control action is needed. Choose the

second relay position as #4 for Direct acting control action. Set the pulse frequency to the

maximum frequency allowed for the particular pump being used, typically 60 to100 pulses/

minute. Control action will produce this frequency at 100% output.

CAUTION: Setting the Pulse Frequency too high may cause the pump to overheat.

Analog – If using Analog control, change "Relays" to "Analogout" using up/down arrow keys.

Choose the ﬁrst Analogout position as #1 if Reverse control action is needed. Choose the

second Analogout position as #2 for Direct control action. Select the analog output current range

required by the control device, 4-20 or 0-20 mA. Press [ENTER].