beautypg.com

10 alarm functions, These values. see table 10, Alty – Watlow Series 935B User Manual

Page 27: During auto-tuning. see table 10, Table 10, Required for operation. see table 10, Ahys, Alty] [ahty, Denc] [deno] [prnc] [prno, Ahy5

background image

Set Point

Deviation
normally
closed

Deviation
normally
open

Process
normally
closed

Process
normally
open

Non-Alarm State
LED off
Alarm Output:

Alarm State
LED on
Alarm Output Status:

Function

A deviation alarm
tracks set point.

A process alarm
is a fixed value,
independent
of set point.

Alarm High Region

Alarm Low Region

Safe
Area

Safe
Area

Alarm Type

Alarm Hysteresis is the change in the process variable (actual)
required to clear the alarm relay after an alarm occurs.

Alarm High Region

Alarm Low Region

0

Silenced-Alarm State
LED off
Alarm Output Status:

Power-Off State
LED off
Alarm Output Status:

Deviation Alarm

Process Alarm

Watlow Series 935B User’s Manual 27

Table 10 - Alarm Functions

Note: With no power connected to the unit, the alarm output will be in an open state.

To Clear an Alarm that is latched or “silence-able’ requires the operator to press the

ß

key after

the process returns to a safe, or non-alarm condition. Non-latching alarms self-clear. See Table 11:

[`LAt]

and

[`SIL]

, p. 29.

Table 10 (below) and Table 11 (p. 29) illustrate the Series 935B alarm features.

[denc]

[deno] [prnc]

[prno]

[ahy5]

[ahy5]

[alty]

[ahty]

[ahy5]

[ahy5]

[`al0]

[`al0]

[`ah1]

[`ah1]