Application: level indicator and solid-state switch output

The loop current provides:

a reading proportional to level, within the 0 - 100% range, at menu 00 or 10 on the device, or at a remote indicator

an out-of-range signal ooL alternating with PV if the level is above URV or below

LRV

The solid-state switch is activated at Upper Threshold Setting and deactivated at Lower Threshold Setting. In the diagram below, it is used to activate a pump via an auxiliary power circuit.

The activation and deactivation can be modified by Upper and/or Lower Threshold delays (menus 13 and 14).

The reading can be stabilized if necessary by applying Damping (menu 0A): the update value for Damping is controlled by menu 09.

Example: The level is to be held between 90% and 8%.

 

Indicator: primary variable viewed at menus 00 or 01;

 

0-100%units or% selected in menu 01

auxiliary

 

 

 

 

 

 

 

solid-

power

 

 

 

pump

 

current loop connection

 

state

 

Active Shield section

 

output

power

 

 

P

 

 

 

 

 

 

(menu 0C) USL

 

75.8 pF

 

 

 

 

 

 

(menu 0F) URV = 100%

 

 

 

 

Upper Threshold Setting = 90%

 

 

 

solid-state

menu 15 (activation hysteresis)

 

 

 

switch

 

 

 

 

output:

 

 

 

 

selected at

 

 

 

 

menu 17

menu 16 (deactivation hysteresis)

 

 

 

and

 

 

 

Lower Threshold Setting = 8%

 

 

 

controlled

 

14.3 pF

 

(menu 0E) LRV = 0%

 

 

by menus

 

 

13 to 18.

(menu 0B) LSL

 

 

 

Device settings:

 

 

(The device is first restored to factory settings before being commissioned)

 

TV0 selected: Transmitter Variable 0 is PV

Menu 01 reads

Pv = 0

Lower Range Value (0% of range) is set to 14.3

Menu 0E reads

14.30

Upper Range Value (100% of range) is set to 75.8.

Menu 0F reads

75.80

Current loop is in analog mode, with both buttons pressed

Menu 07 reads

C:An

Solid-state switch enabled, contact closed selected

Menu 17 reads

S:cc1

Activation hysteresis is set to 90.

Menu 15 reads

90.0

Deactivation hysteresis is set to 8.

Menu 16 reads

08.0.

When the level reaches 90%, the solid-state output is closed and the pump is started via the auxiliary circuit. When the level drops to 8% the solid-state output is opened, the auxiliary circuit is deactivated, and the pump stops.

1.S:cc appears while the button is pressed. See menu 17 on page 70 for more details.

7ML19985GE01

SITRANS LC 500 – INSTRUCTION MANUAL

Page 93

Appendix E

Page 99
Image 99
Siemens Sitrans, LC 500 instruction manual Device settings, CAn, 90.0, 08.0