BABBITT LS8500 User manual

www.babbittinternational.com Reference Manual
2020 Rev.2
LS8500 Presence/Absence Switch
OWNERS MANUAL
♦INSTALLATION
♦CALIBRATION
♦TROUBLESHOOTING
♦WARRANTY
P.O. Box 70094
Houston, TX 77270
[phone]

www.babbittinternational.com Reference Manual
2020 Rev.2
TABLE OF CONTENTS
Page
1. Description -------------------------------------------------------------------- 1
A. General Description ------------------------------------------------ 1
B. Specifications ------------------------------------------------------1-2
2. Theory of Operation/ Ordering Information ------------------------------ 3
3. Installation ---------------------------------------------------------------------3
A. Inspection ------------------------------------------------------------ 3
B. Physical Installation of Probe ------------------------------------- 3
C. Installing the Receiver ----------------------------------------------4
D. Typical Applications and Wiring Diagrams -------------------5-7
1) LS8000 Terminal Layout --------------------------------5-7
2) Ladder Diagrams ------------------------------------------5-7
4. Calibration -------------------------------------------------------------------- 8
A. Setting the Time Delay -------------------------------------------- 8
B. Fail Safe Selection -------------------------------------------------- 8
C. Sensitivity Calibration --------------------------------------------- 9
5. Maintenance and Troubleshooting ------------------------------------- 9-10
6. Warranty -----------------------------------------------------------------------11

www.babbittinternational.com Reference Manual
2020 Rev.2
Read this manual before working with the product. For personal and system safety, and for optimum product
performance, make sure that you thoroughly understand the contents before installing, using or maintaining this
product.
For equipment service or support needs:
Customer Service: 1-800-835-8012 or 713-467-4438 (8:00 a.m. to 5:00 p.m. CST US)
Failure to follow safe installation and servicing guidelines could result in death or serious injury.
Make sure only qualified personnel perform the installation.
Use the equipment only as specified in this manual. Failure to do so may impair the protection provided by the
equipment.
Do not perform any services other than those contained in this manual unless you are qualified.
Explosions could result in death or serious injury.
Verify the operating environment of the Babbitt LS8500 Presence/Absence switch is consistent with the
appropriate location certifications.
Do not remove the housing cover in explosive atmospheres when the circuit is alive.
To prevent ignition of flammable or combustible atmospheres, disconnect power before servicing.
High voltage that may be present on leads could cause electrical shock.
Make sure the main power to the Babbitt LS8500 Presence/Absence switch is off and the lines to any other external
power source are disconnected or not powered while wiring the instrument.
WARNING
NOTICE

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2020 Rev.2
LS8500 PRESENCE/ABSENCE SWITCH
1. DESCRIPTION
A. General Description
The LS8500 is a point level switch that detects the presence or absence of material in a pipe. The basic
unit is made up of a solid stainless steel flange attached to an explosion proof housing. Inside the
explosion proof housing is a transmitter that is connected to the receiver board by a twisted, shielded pair
of wires. The receiver board may be mounted up to one mile from the flange. All calibration adjustments
and indicators are at the receiver. The receiver also has the relay output and an on board fuse. The unit is
calibrated in the absence of material and an on board relay at the receiver changes state when material is
detected.
B. Specifications
Electrical
Power: 115 VAC (±15%) 50/60 Hz. 2 watts, standard.
(12 VDC, 24 VDC or 230 VAC optional)
Output: 2 Form C contacts, DPDT relay, 5 amp resistive
at 125, 250 VAC; 30 VDC
Fuse: On board, 250 mA @ 125 volts
Fail Safe: Selectable high or low level
Time Delay: Selectable: ON or OFF delay
Adjustable: 1/8 sec to 2 hrs.
RF Frequency: Approximately 1.3 MHz
Environmental
Hazardous Area: Transmitter: Housing is CSA and UL approved for Class I, Div. 1,
Groups C & D; Class II, Groups E, F & G
Receiver: Open printed circuit board can be put in
enclosure as required by application.
Temperature: Probe: -30° F to 180° F**
Electronics: -40° F to 185° F**
Pressure: Probe: 200 PSI @ 75° F**
(**Higher ranges available upon request)
Construction: Probe: All wetted parts, 316 SS Teflon (or UHWMPE) and Viton.
A Halar coating can be applied to the flange when applicable.
Transmitter: Housed in cast aluminum explosion proof enclosure
Receiver: Printed circuit board mounted on plastic track provided
with each unit.
Specifications subject to change without notice.
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2020 Rev.2
C. Ordering Information
LS8500 -115VAC - FP - 4” 150# - PR
Model #
(LS8500)
Power Supply:
(115VAC 24VDC 12VDC 220VAC)
Sensor Type:
(FP-Flange Probe or TC-Tri-Clamp)
Sensor Size:
Flange Model:
(PR-Partial Ring or FR-Full Ring)
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2020 Rev.2
2. THEORY OF OPERATION
The LS8500 employs a radio frequency (RF) balanced impedance bridge circuit to detect if the sensing
element is in contact with the material that is to be sensed. When material is not in contact with the sensing
element, the bridge is balanced by turning the adjustment pot to find the threshold where the red led goes out.
When material is in contact with the sensing element, the bridge becomes unbalanced and the comparing
circuit realizes the change. This causes the relay to change state.
3. INSTALLATION
A. INSPECTION
After unpacking the LS8500, visually inspect the unit for any damages.
Please advise the factory or your local distributor of any damage.
A complete unit should consist of the following:
1. An explosion proof enclosure with flange attached
2. A transmitter module in the explosion proof enclosure
3. The LS8000/R receiver card
4. A plastic snap track to mount the receiver card
NOTE: LS8000 AND LS8500 ELECTRONIC COMPONENTS ARE INTERCHANGABLE.
B. PHYSICAL INSTALLATION OF TRANSMITTER MODULE AND PROBE
1) The LS8500 is installed into the pipe using a flange.
2) CAUTION: Always take the necessary safety precautions when cutting or welding in the
coupling for the LS8500.
a) Tag and lock out the electrical power to the equipment that services the vessels.
b) Check liquid or dry powders that create a gas in the vessel for oxygen as well as the
explosion factor. (All dust will explode.)
c) Vessels that are cross vented have to be isolated.
3) Tighten the LS8500 flange into place using proper gaskets and sufficient torque to prevent leaks.
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CAUTION: ALL INSTALLATION AND WIRING MUST CONFORM TO NEC AND ALL
OTHER LOCAL ELECTRICAL CODES. TAKE SPECIAL CARE IN OBSERVING
HAZARDOUS AREA SAFETY PROCEDURES. WE ASSUME NO LIABILITY FOR
IMPROPERLY INSTALLED OR WIRED UNITS.

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2020 Rev.2
NOTE: LS8000 AND LS8500 ELECTRONIC COMPONENTS ARE INTERCHANGABLE.
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www.babbittinternational.com Reference Manual
2020 Rev.2
NOTE: LS8000 AND LS8500 ELECTRONIC COMPONENTS ARE INTERCHANGABLE.
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2020 Rev.2
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2020 Rev.2
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2020 Rev.2
4. CALIBRATION
PLEASE READ THE ENTIRE CALIBRATION PROCEDURE BEFORE CALIBRATING THE LS8500.
If no time delay is required, turn the time adjustment pot completely CCW and set S1 down, S2 up. The
potentiometer has 20 turns and freewheels at the end of its travel without damage. You may hear “clicks” at
the end of travel.
A. Setting the Time Delay
1) Setting the timing mode, either on delay or off delay, is done by positioning S3 and S4 as shown in the
chart below.
NOTE: S3 and S4 also select fail safe high level (FSH) or fail safe low level (FSL).
2) Select the timing range using S1 and S2 as shown on the chart below.
3) Adjust the time adjustment potentiometer clockwise to increase time or CWW to decrease until the
exact time delay is reached. The test switch may be depressed to start the timing when checking timing
sequence.
NOTE: For long timing ranges you can set the timer for a shorter range, then
change the range switches (S1 and S2) to increase the time. For example, the desired
time delay is 15 minutes. This is equal to 900 seconds. By setting S1 down and S2 up
and adjusting the timer to approximately 28 seconds, the ratio on this range is 1. To
increase this range by 32, move S1 up and S2 up. 32x28 seconds equals approximately
15 minutes.
B. Fail Safe Selection
The failsafe feature provides a “false alarm” in case of power outage or major component failures. When
properly selected, the failsafe feature can protect equipment or alert you of a unit failure.
1) Fail Safe High (FSH) means that the relay is energized when NO PRODUCT is touching the
sensing element. The green led indicates relay status and is on when the relay is energized. When
product comes into contact with the sensing element, the relay is de-energized.
2) Fail Safe Low (FSL) means that the relay is energized when PRODUCT IS touching the sensing
element.
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NOTE: Due to the wide variety of applications and possible control or alarm functions, the proper
fail safe selection will depend on your circumstances. Please call your distributor or the factory if
you need assistance.

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2020 Rev.2
C. Sensitivity Calibration
The LS8000 should be calibrated when no material is touching the sensing element and when the unit is
installed where it will be used.
1) Observe the red LED. If it is on, go to step 3.
2) If the red LED is off, turn the sensitivity adjustment potentiometer CW until it comes on.
3) Turn the sensitivity adjustment pot CCW until the red LED just goes out and continue to turn the pot
CCW at least ¾ of a turn. This sets the unit to its maximum stable sensitivity. If in your application
this is too sensitive, you can turn the sensitivity adjustment pot further CCW. Always bring the
product into contact with the sensing element after calibration to assure proper performance.
Note the green LED indicates relay status. The relay is energized when the green LED is on.
SPECIAL CALIBRATION NOTES:
For some products, the LS8000 can be calibrated with product touching the sensing element. To do
this, turn the sensitivity adjust pot CW until the red LED just comes on and continue CW for ¼ to ½ of
a turn.
ALWAYS CHECK TO SEE IF THE UNIT RESETS IN THE ABSENCE OF PRODUCT.
5. MAINTENANCE AND TROUBLESHOOTING
No routine maintenance is required other than keeping the interior of the unit clean and free of dirt, dust and other
contaminants.The LS8500 consists of three main sub-assemblies. These are the enclosure with the flange probe, the
transmitter module and the receiver card. The following troubleshooting guide will assist in determining how to
correct most of the problems which may occur in the field. Review the Installation and Calibration procedures in
sections 3 and 4.
See NEXT PAGE FOR TROUBLESHOOTING…………………..
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www.babbittinternational.com Reference Manual
2020 Rev.2
PROBLEM POSSIBLE CAUSE SOLUTION
RED LIGHT cannot be Transmitter module not connected Plug transmitter into flange.
adjusted to turn on. to flange.
No power to unit. Check for correct power.
Blown on-board fuse. Replace fuse.
Bad receiver card. Repair or replace card.
RED LED remains on at all Flange is shorted to ground. Unplug banana plug and position
it so that the bare end is not
touching anything. Turn calibration
Pot 20 turns CCW. LED should go
out. If it does, repair, replace or
clean flange. If LED does not go out,
replace electronics.
Check shielded cable for proper
connection.
Check shielded cable for shorts or
open circuits.
Unit triggers when material Improper mounting of flange. Contact factory or distributor.
touches sensing element, Improper calibration procedure. See Section 4 C.
but will not reset when Excessive material build-up on Perform “dirty pipe calibration”;
material recedes from sensing element. Recalibrate with built up material
sensing element / unit and on sensing element. See section 4C.
gives false alarm.
Revise mounting or use time delay.
See section 4C.
Unit will not detect material. Improper calibration. See calibration instructions,
Section 4.
Transmitter module not plugged Plug transmitter module into probe.
into probe. Be sure material is not touching
Unit was calibrated with material sensing element and recalibrate.
touching sensing element.
Unit will not stay in Poor grounding of transmitter Provide secure ground connection.
calibration housing to vessel.
Relay operates properly, but Burned or broken lands on receiver Turn off power. Remove module
no signal at terminals. printed circuit board. from housing and inspect lands
On printed circuit for damage.
Replace if necessary.
Bad relay contacts. Replace relay or return for repair.
PLEASE CONTACT THE FACTORY OR YOUR DISTRIBUTOR IF YOU HAVE ANY
QUESTIONS OR NEED ASSISTANCE
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www.babbittinternational.com Reference Manual
2020 Rev.2
6. WARRANTY
All components of the LS8500 are warranted to be free from defects in material and workmanship for a
period of two years from the date of purchase. This warranty applies to general purchaser and to
components installed, serviced and operated according to instructions.
Babbitt International, Inc. will repair or replace, at its option, FOB at its plant or any other location
designated, any part which proves to be defective in manufacture or workmanship.
All claims must be made in writing within the warranty period. No claims outside of the warranty period
will be honored.
Warranties are not applied to any components which have been damaged by improper installation, use,
exposure to unusual atmospheric conditions or components which have been misused, abused, damaged
by neglect or accident. This warranty shall not apply to any components which have been altered or
repaired without the prior written consent of Babbitt International, Inc.
Babbitt International, Inc. assumes no responsibility or liability for any labor or material back charges,
without written authorization. Any products returned must be with prior written authorization.
THE FOREGOING IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR
IMPLIED,INCLUDING ANY WARRANTIES OF MERCHANTABILITY AND/OR FOR FITNESS FOR
PARTICULAR PURPOSE, AND BABBITT INTERNATIONAL, INC. ASSUMES NO OTHER
LIABILITIES EXPRESSED OR IMPLIED. BABBITT INTERNATIONAL, INC. SHALL NOT BE LIABLE
FOR NORMAL WEAR AND TEAR, NOR FOR DIRECT, INCIDENTIAL OR CONSEQUENTIAL
DAMAGES. IN NO EVENT SHALL BABBITT INTERNATIONAL INCORPORATED’S LIABILITY
EXCEED THE PRICE OF ITS PRODUCT AT THE TIME OF PURCHASE.
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