Alarms; Eb Function; Hold Function; Flash Function - gefran 40B 48 User Manual

The standard device is produced with parameter C.I.= 8,
with sampling time of 120 msec and Eb function disabled.
The Eb function lets you detect if the probe power supply is interrupted. This function is valid for probe currents > 20mA (8mA
in version 2.0x)
Example:
- probe voltage 10V
- strain-gauge resistance 350Ω
- current =
or for three probes connected in parallel
- probe voltage 10V
- strain-gauge resistance 350Ω
- corrente =
The input value and alarms are frozen while the logic input is active.
With the logic input active, a reset turns OFF both the relay outputs and the alarms latch.
Input value is sampled; state of alarms is not transferred to outputs; outputs are "frozen".
When the logic input is active the input value is "frozen" and the outputs are updated according to the calculated alarms
state, including the ones latched.
Normal absolute alarm
AL2
AL1
(*)
alarm 1
alarm 2
For AL1 inverse absolute alarm (min.) with positive H1, 1 t = 1
(*) = OFF if disabling on power-on exists
For AL2 direct absolute alarm (max) with negative H2, 2 t = 0
Normal deviation alarm
(AL1 absolute, AL2 relative)
AL1+AL2
AL1
alarm 1
alarm 2
For AL1 direct absolute alarm (max) with negative H 1, 1 t = 0
For AL2 direct relative alarm (max) with negative H2, 2 t = 2
6
V 10
≅ 28mA
=
R 350
V 10 30
≅ 85mA
= =
R 350 350
3

• HOLD function

• FLASH function

AL2 + H2
AL1 + H1
time
AL1 + AL2 + H2
AL1 + H1
time

• Eb Function

6 • ALARMS
AL1
inverse
direct
For AL1 inverse absolute, symmetrical alarm with hysteresis H1, 1 t = 5
For AL1 direct absolute, symmetrical alarm with hysteresis H1, 1 t = 4
AL1+AL2
AL1
AL1-AL2
alarm 1
alarm 2
For AL1 direct absolute alarm (max) with negative H1, 1 t = 0
For AL2 symmetrical deviation alarm H2, 2 t = 6
Symmetrical absolute alarm
AL1 + [ H1 ]
AL1 - [ H1 ]
time
Symmetrical deviation alarm
(AL1 absolute, AL2 relative)
AL1+AL2+H2
AL1+H1
time
81651C_MHW_40B48-96_0308_ENG