Tecfluid LD61N User Manual
Page 5
7. TECHNICAL
CHARACTERISTICS
Materials
:
Fork: EN 1.4404 (AISI 316L). Others on demand.
Housing:
Polycarbonate.
Process connection
:
Threads G1 (BSP), 1” NPT, DIN 11851, Clamp ISO 2852
Model
:
NAMUR (IEC60947-5-6, EN50227)
Switching time:
≈ 1s
Hysteresis
:
± 2 mm with H
2
O
Operation limits:
Viscosity: up to 10.000 cSt
Density: > 0.6 kg / l
Process temperature (liquid). -30 ... 115ºC
Ambient temperature: -5 ... 40ºC
Standard pressure: PN25
Ingress Protection:
IP65
6. MAINTENANCE
The working life of the vibrating fork depends basically on the abrasive characteristics of
the product used.
The LD61N detector only needs maintenance when the product, which can adhere to the
tines, will not let the detector change to a non detection state. In these cases the tines
must be cleaned.
6.1 Cleaning
To clean the tines, a brush suitable for removing the incrusted product must be used. You
should not try to knock off the adhered product from the tines.
During the cleaning process, be careful not to apply force against the tines as this can
bend them and damage the detector beyond repair.
5
operation and the amplifier circuit can detect the state of the connection line to the NAMUR
device.
In the NAMUR LD61N device, the four possible stable states are the following:
1.
Open circuit:
It occurs when the connection between the amplifier circuit and the
NAMUR device is broken. The output current of the amplifier circuit will be equal or
less than 0.05 mA.
2.
OFF state of the NAMUR device:
The output current of the amplifier circuit will be
from 0.35 mA to 1.2 mA.
3.
ON state of the NAMUR device:
The output current of the amplifier circuit will be
from 2.1 mA to 6.03 mA.
4.
Short circuit:
It occurs when there is a short circuit in the connection between the
amplifier circuit and the NAMUR device. The output current of the amplifier circuit will
be more than 7.45 mA. The resistance between terminals will be less than 100
Ohms.
NOTE:
the current values are calculated by using a nominal voltage value of 8.2V and an
amplifier output resistance of 1k, and the limits for the resistance between terminals
specified in the standard (from 100 to 360 Ohms).