Data sheet
Liquid Level Switch
Type LLS 4000/4000U
|
|
|
The LLS 4000/4000U liquid level switch is |
|
|
|
|
||
|
|
|
designed to detect the state (gas or liquid) of the |
|
|
|
|
refrigerant in front of the sensing head, while |
|
|
|
|
installed in a wide range of refrigeration |
|
|
|
|
applications. |
|
|
|
|
The LLS level switch comes in 2 variants, LLS 4000 |
|
|
|
|
and LLS 4000U. They are identical except for the |
|
|
|
|
connector thread interface to the system. The LLS |
|
|
|
|
4000 is provided with G3/4" thread, while the LLS |
|
|
|
|
4000U is provided with NPT 3/4" thread. |
|
|
|
|
The LLS 4000/4000U liquid level switch is based |
|
|
|
|
on the proven reflectometry measuring |
|
|
|
|
technology(microwave level measurement) |
|
|
|
|
adapted specifically for the new LLS 4000/4000U |
|
|
|
|
switch. |
|
|
|
|
LLS 4000/4000U liquid level switches can be used |
|
|
|
|
to control the liquid level of many different |
|
|
|
|
refrigerants in vessels, accumulators, receivers, |
|
|
|
|
standpipes, etc. |
|
|
|
|
The switches are normally installed in a pair of |
|
|
|
|
two, controlling the upper liquid level and the |
|
|
|
|
lower liquid level. |
|
|
|
|
The level switch includes a relay that switches by |
|
|
|
|
change in refrigerant state. The on site |
|
|
|
|
configuration of the LLS allows the normally |
|
|
|
|
open/closed relay setting depending on the |
|
|
|
|
desired correlation. |
|
|
|
|
For SIL applications a SIL2 version is available |
|
|
|
|
with blocked configuration (not configurable). |
|
|
|
|
All configuration and readings from the LLS |
|
|
|
|
switch are performed through Bluetooth and a |
|
|
|
|
downloadable special Danfoss app. |
|
|
|
|
|
|
Features |
• |
Plug and play liquid level switch |
• Approvals: CE, PED, EMC, RED, ROHS, SIL2, FCC, |
|
|
• |
Easy installation and minimum or no need for |
( EAC, IC pending) |
|
|
configuration |
• Conforms to: |
||
|
• Convenient communication with all units via |
Telecommunications Directive RED 2014/53/EU. |
||
|
Bluetooth and a Danfoss app |
|||
|
Low voltage directive 2014/35/EU. |
|||
|
• |
SIL2 compliant version |
||
|
EMC directive 2014/30/EU. |
|||
|
• 2 commonly used connection variants |
|||
|
ROHS 2011/65/EU |
|||
|
• |
Maintenance free |
||
|
|
|
• Replacement of electronic part without removing mechanical part (no opening to refrigerant)
• Applicable for ammonia and commonly used H(C)FCs
• Well proven reflectometry measuring principle
© Danfoss | DCS (ms) | 2020.02 |
AI323832972563en-000101 | 1 |
Data sheet | Liquid Level Switch, type LLS 4000/4000U
Contents |
Features . . . . . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
1 |
|
Product concept/applications . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
3 |
|
Connection types . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
4 |
|
Measuring principle . . . . . . . . . . . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
4 |
|
Electrical installation/connection . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
5 |
|
|
LED light indicators . . . . . . . . . . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
5 |
|
Configurable parameters . . . . |
. . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
5 |
|
Ordering . . . . . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
7 |
|
Dimensions and weights . . . . . . |
. . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
. 7 |
|
Maintenance/service & calibration precautions . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
8 |
|
|
Bluetooth communication . . . . . |
. . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
8 |
|
Bluetooth configuration . . . . . . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
9 |
|
Technical data . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
10 |
|
Safety/ Approvals . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
11 |
2 | AI323832972563en-000101 |
© Danfoss | DCS (ms) | 2020.02 |
Data sheet | Liquid Level Switch, type LLS 4000/4000U
Product concept/ applications
To control if a liquid level is within predefined allowed limits, two LLS 4000 are installed in an upper and a lower limit position respectively. By this setup the liquid level is between the two level switches and the lower switch will sense liquid, while the upper will sense gas.
In case the liquid level moves outside the limits, one of the switches will sense opposite and switch the built-in relay. This relay switch function should be used for alarm settings. This is made easy when connected to the system PLC.
|
SVA |
SVA |
|
|
|
|
|
|
|
AKS 4100 |
|
|
|
SFA |
|
|
|
|
EKE |
|
+DSV |
|
|
|
|
|
|
|
|
|
|
347 |
|
|
|
|
SVA |
|
|
|
|
|
|
|
|
|
|
|
|
|
LLS 4000 |
LLG |
|
|
|
|
|
|
|
ICF 25-6-5A |
|
|
|
|
|
|
|
|
|
|
|
LLS 4000 |
|
|
|
|
|
|
|
SNV |
|
|
SVA |
|
|
|
SVA |
|
|
|
SCA-X |
|
|
SCA-X |
|
SVA |
|
|
|
|
|
|
||
|
|
|
|
FIA |
|
|
|
|
|
|
BSV |
|
|
|
|
|
|
|
|
|
|
|
BSV |
|
|
|
|
FIA |
SNV |
|
|
|
SNV |
SVA |
|
|
|
SNV |
|||
|
|
|
QDV |
|||
|
|
|
|
|
|
|
|
RT |
|
RT |
|
|
15 |
|
|
|
|
|
||
|
260A |
|
260A |
SNV |
|
|
SNV |
SNV |
|
|
|
|
|
|
|
|
SNV |
|
||
|
|
|
|
|
||
|
SVA |
|
SVA |
|
|
|
Upper
LLS 4000/U
Liq. Level
Lower
LLS 4000/U
The LLS can be used wherever liquid levels of ammonia and certain H(C)FC refrigerants must be controlled.
The LLS comes in 2 versions:
-A standard version, which is applicable for most refrigeration or processing plants, and is fully configurable regarding type of liquid and relay setting.
-A SIL2 version applicable for SIL compliant process plants. This version is non-configurable regarding relay setting (see section: Configurable
parameters) and is intended specific as the upper level switch.
© Danfoss | DCS (ms) | 2020.02 |
AI323832972563en-000101 | 3 |
Data sheet | Liquid Level Switch, type LLS 4000/4000U
Connection types |
Beside the 2 versions the LLS also comes with 2 |
|
different thread types , LLS 4000 and LLS 4000U. |
|
They are identical except for the connector |
|
thread for installation to the system. The LLS |
|
4000 is provided with G3/4" thread, while the LLS |
|
4000U is provided with NPT 3/4" thread. |
For connection to the actual part of the system appropriate weld connectors are needed. NPT connectors are widespread available, while Danfoss offers weld connectors for G3/4" thread as accessory.
Please note geometric restrictions below.
|
|
Weld |
|
LLS 4000 |
G 3/4” |
connector |
|
|
|
||
LLS 4000U |
NPT 3/4” |
|
|
|
|
max |
|
|
|
45 mm |
|
|
|
1.8 in |
min |
|
|
|
|
|
|
|
25 mm |
|
|
|
1 in |
Measuring principle |
The measurement principle of the LLS is based |
|
on reflectometry with a 4.9 GHz to 6.2 GHz |
|
linear sweep (Microwave switch technology). |
|
The reflected signal is characterized by a |
|
resonance frequency. The resonance frequency |
|
in air is taken as a reference (fref). When the |
|
sensing element is in contact with the liquid, |
|
the resonance frequency is shifting to a lower |
|
frequency. This is due to the change of the |
|
dielectric constant of the medium. |
The point level switch monitors the resonance frequency and indicates whether the sensing element is surrounded by liquid or gas.
The figure below shows the reference frequency with air (dielectric constant εr=1) in front of the sensing element and with a liquid dielectric constant εr> 1.35.
PR
∆f ~ εr
with |
without |
liquid |
liquid |
f
4.9 GHz fliquid fref 6,2GHz
© Danfoss | DCS (ms) | 2020.02 |
AI323832972563en-000101 | 4 |