Omega TF280-N User manual

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TF280-N/ TF280-P
Tuning Fork Level Switch

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Contents
1. Models…………………………………………………………………….……….……4
2. Wiring …………………………………………………………………….….…………5
3. Fork Sensing Spot........................................................................................................ 6
4. Magnetic Test................................................................................................................ 6
5. Output Status ................................................................................................................ 7
6. Installation...……………………………………………………………………………8
7. Simple Troubleshooting............................................................................................. 9

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1. Models

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2. Wiring
Power supply is DC. Output is PNP / NPN. Please see Figure 1.
DIN & Cable Wiring:
PNP Output:
High(Max.) Mode: No. 1 pin(Brown) is connected to N-. No.3
pin(Blue) is connected to L+. Output is connected to No. 2
pin(Black), then connected to N-. No. 4 pin(Yellow Green) goes to
ground.
Low(Min.)Mode: number 1 pin(Brown) is connected to N-.
No.2 pin(Black) is connected to L+.
Output is connected to No. 3 pin(Blue), then connected to N-.
No.4 pin(Yellow Green) goes to ground.
NPN Output:
High(Max.) Mode: No. 1 pin(Brown) is connected to L+. No.3
pin(Blue) is connected to N-. Output is connected to No. 2
pin(Black), then connected to L+. No. 4 pin(Yellow Green) goes to
ground.
Low(Min.)Mode: No. 1 pin(Brown) is connected to N-. No.3 pin
(Blue) is connected to L+. Output is connected to No.2 pin
(Black), then connected to L+. No. 4 pin(Yellow Green) goes to
ground.

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3. Fork Sensing Spot
TF280-N/TF280-P fork sensing spot is shown as Figure 3 below. Considering
testing medium is water (S.G.=1 g/cm3) , sensing spot is at the fillister about
23mm from the tip. If testing medium has S.G. lower than 1g/cm3, sensing spot
would be above the fillister. In contrast, sensing spot will be below the fillister.
4. Magnetic Test
After the switch is installed and powered, magnetic test function can be
performed accordingly. The testing point is marked on the housing label. User
holds the magnet and moves it close to testing point, the output status will switch
from NO. to NC. or NC to NO. and red LED would switch ON or OFF while fork
continues to vibrate. When magnet is pulled away from the testing point, the
output status and red LED would return as default while fork continues to vibrate.
The purpose of testing is to confirm the wiring and functioning are correct.

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5. Output Status
TF280-N/TF280-P is equipped with 12~55 Vdc, top of housing would light up
with green LED.
DIN & Cable type:
Low(Min.) Mode: Tuning fork switch will be actuated 3 seconds after the
power is on. Relay is NO and red LED indication is on. When tuning fork
is covered by testing medium, vibration stops and relay becomes NC.
Red LED indication is off.
High(Max.) Mode: Tuning fork switch will be actuated 3 seconds after the
power is on. Relay is NC and red LED indication is on. When tuning fork
is covered by testing medium, vibration stops and relay becomes NO
Red LED indication is off.
Flashing red indicates abnormal: Possible causes overloads or shortcircuit
load back, equipment malfunction or wear tuning fork probe.

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6. Installation
Horizontal Installation:
1. Can be applied in viscosity, powder and, liquid. Do not inst.(Figure 1)
2. When installing the product, The position hole plug must be upward
direction.
If not, incorrect installation could be damage the product.( Figure 2)
(Figure 1) (Figure 2)
Vertical Installation:
1. Opening of the two fork blades is to be as the flow direction. ( Figure 3)
2. Do not install near substance inlet. ( Figure 4)
(Figure 3)
(Figure 4)

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7. Simple Troubleshooting
Error
Cause
Solution
Power Supply indicator
(Green Light) is off and
the switch is not
conductive.
No power supply.
Power on or check the wiring
and repair.
Power doesn't meet the
specification.
Check the nameplate and
power 12 to 55 Vdc
The signal lamp is
normal and the switch
output is incorrect.
The control circuit wiring
is incorrect.
Check the wiring diagram
and correct it.
The wiring for high/low
level is incorrect.
Check the wiring and repair.
Output Indicator (Red
Light) is flashing.
The tuning fork is worn,
deformed or demaged.
Contact with the local sales
representative.
The tuning fork sensed
the material, but the
switch indicates it does
not exist.
Liquid density sensed
< 0.7g/cm³, the selected
model is not applicable
to use
Contact with the local sales
representative.
The tuning fork does
not sense the material,
but the switch indicates
it exists.
The tuning fork is stuck or
agglomerated by the
material.
Check the tuning fork and
remove the sediment.

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M5733/0119