1. Introduction
Thank you for selecting the Extech VFL Process Controller. The VFL series uses intelligent
algorithms (including fuzzy logic) to offer highly precise process control. The wide array of
features and functions are easily configured in the four program menu levels.
Controller Wiring
The controller must be wired before use. Inputs, outputs, and AC power are connected on the
rear terminals as described in the Wiring section.
Process Inputs
The VFL series can be ordered in a variety of input configurations. For temperature versions,
the controller accepts a thermocouple or RTD thermometer. For analog versions, the
controller accepts a 4 to 20mA or 1 to 5V dc process signal.
PV (Process Variable) Display
Process inputs values are displayed on the PV (Process Variable) digits on the front panel.
Control Outputs
The VFL series offers three control output options: mechanical relay, pulsed DC Trigger
(24VDC), and analog (4-20mA). Relay and Trigger outputs are ON-OFF control types (pulsed).
The 4-20 output, on the other hand, is a linear signal corresponding to the 0 to 100% output.
Alarm Outputs
The Alarm relays can be used to perform a variety of alarm and timer functions. Alarms can
be used to shut down power in the event of an emergency, switch on an alert signal, control
other variables in a process, and more. Alarm relays can also function as ON and OFF timers.
Setting Value (SV)
The Setting Value (SV), also known as the Setpoint, is the target point for your process. The
SV is changed using the arrow keys. The SV is displayed on the lower LED digits in green.
Programming Menus
The controller has five Programming Menu Levels. Each menu includes a series of
customizable control and tuning parameters.
Tuning the Controller
The controller’s PID settings must be tuned for each application. Run the Auto Tune utility
after the controller is wired and ready for use. Manual tuning adjustments can also be made.
Tuning is key to a stable process.
Contact Extech
Visit the Extech website www.extech.com for customer support, up-to-date user
documentation, and full warranty information. This device is covered by a 2-year limited
warranty.
To Next Page
Loading...
Need help?
General
