Specifications are subject to change without notice (12.12.05)
1
Monitoring Relays
Frequency Monitoring
Types DFB01, PFB01
Over/under frequency monitoring relays
Measuring if power supply frequency is within set limits
Measure on own power supply
Measuring ranges
Voltage: 24 to 240 VAC
Frequency: 50 - 60 Hz
Separately adjustable upper/lower level on relative
scale
Adjustable delay on alarm or on recovery (0.1 to 30 s)
Programmable latching or inhibit at set level
Output: 8 A SPDT relay N.D. or N.E. selectable
For mounting on DIN-rail in accordance with DIN/EN
50 022 (DFB01) or plug-in module (PFB01)
22.5 mm Euronorm housing (DFB01) or 36 mm
plug-in module (PFB01)
LED indication for relay, alarm and power supply ON
Product Description
Ordering key
DFB 01 C M24
Housing
Function
Type
Item number
Output
Power Supply
DFB01 and PFB01 are pre-
cise frequency monitoring
relays. The relays monitor
their own power supply from
24 to 240 VAC.
The advantage of using the
latch function is that the
relay can be kept energized
even after the end of the
alarm condition. Inhibit func-
tion can be used to avoid
relay operation when not
desired (maintenance, tran-
sitions). The LED's indicate
the state of the alarm and
the output relay.
Type Selection
Mounting
Output
Measuring range
Supply: 24 to 240 VAC
DIN-rail
SPDT
50-60 Hz
DFB 01 C M24
Plug-in
SPDT
50-60 Hz
PFB 01 C M24
Input Specifications
Output Specifications
Input
Own power supply DFB01:
A1, A2 (24 to 240 VAC)
PFB01:
2, 10 (24 to 240 VAC)
Measuring ranges
Upper level
Lower level
Selectable by DIP-switches
2 Hz range
-0.2 to +2 Hz -2 to +0.2 Hz
50 Hz
49.8 to 52 Hz 48 to 50.2 Hz
60 Hz
59.8 to 62 Hz 58 to 60.2 Hz
10 Hz range
-1 to +10 Hz
-10 to +1 Hz
50 Hz
49 to 60 Hz
40 to 51 Hz
60 Hz
59 to 70 Hz
50 to 61 Hz
Contact input
DFB02
Terminals Z1, Z2
PFB02
Terminals 8, 9
Disabled
> 10 k
Enabled
< 500
Pulse width
> 500 ms
Hysteresis
2 Hz range
~ 0.05 Hz
10 Hz range
~ 0.25 Hz
Output
SPDT relay
Rated insulation voltage
250 VAC
Contact ratings (AgSnO
2
)
Resistive loads
AC 1
8A @ 250 VAC
DC 12
5 A @ 24 VDC
Small inductive loads AC 15
2.5 A @ 250 VAC
DC 13
2.5 A @ 24 VDC
Mechanical life
30 x 10
6
operations
Electrical life
10
5
operations
(at 8 A, 250 V, cos
= 1)
Operating frequency
7200 operations/h
Dielectric strength
Dielectric voltage
2 kVAC (rms)
Rated impulse withstand volt. 4 kV (1.2/50 s)
DFB01
PFB01
2
Specifications are subject to change without notice (12.12.05)
DFB01, PFB01
General Specifications
Power ON delay
1 s 0.5 s
Reaction time
(input signal variation from
-10% to +10% or from
+10% to -10% of the range)
Alarm ON delay
< 200 ms
Alarm OFF delay
< 200 ms
Accuracy
(15 min warm-up time)
Temperature drift
200 ppm/C
Delay ON alarm
10% on set value 50 ms
Repeatability
0.02 Hz
Indication for
Power supply ON
LED, green
Alarm ON
LED, red (flashing 2 Hz
during delay time)
Output relay ON
LED, yellow
Environment
Degree of protection
IP 20
Pollution degree
3 (DFB01), 2 (PFB01)
Operating temperature
-20 to 60C, R.H. < 95%
Storage temperature
-30 to 80C, R.H. < 95%
Housing dimensions
DIN-rail version
22.5 x 80 x 99.5 mm
Plug-in version
36 x 80 x 94 mm
Weight
Approx. 150 g
Screw terminals
Tightening torque
Max. 0.5 Nm
acc. to IEC 60947
Approvals
UL, CSA
CE-Marking
Yes
EMC
Electromagnetic Compatibility
Immunity
According to EN 61000-6-2
Emission
According to EN 61000-6-3
Mode of Operation
DFB01 and PFB01 monitor
the frequency value of their
own power supply.
Example 1
(Non-latching mode - N.D.
relay)
The relay operates and the
yellow LED is ON as soon
as the measured frequency
exceeds the upper set level
or drops below the lower set
level for more than the set
delay time. The relay releas-
es when the measured fre-
quency comes back within
the upper and lower limits.
The red LED flashes until the
delay time has expired or
the measured value falls off
the limits.
Example 2
(Latching mode - N.E. relay)
The relay operates and the
yellow LED is ON as long as
the measured frequency is
within the upper and lower
limits.
The relay releases and
latches in alarm position as
soon as the measured fre-
quency exceeds the upper
set level or drops below the
lower set level for more than
the set delay time. The red
LED flashes until the delay
time has expired or the
measured value comes back
within the limits. Provided
that the frequency has
dropped below the upper
set level (minus hysteresis)
or exceeded the lower set
level (plus hysteresis), the
relay operates when the
interconnections between
terminals Z1, Z2 or 8, 9 are
interrupted.
Supply Specifications
Power supply
Overvoltage cat. III
Rated operational voltage
(IEC 60664, IEC 60038)
Through terminals:
DFB01: A1, A2
24 to 240 VAC 15%
PFB01:
2,10
24 to 240 VAC 15%
Dielectric voltage
Supply to output
4 kV
Rated operational power
4 W
Adjust the system frequency
setting DIP switch 3 and
select the desired function
setting the DIP switches 1, 2
and 4 as shown on the right.
To access the DIP switches
open the grey plastic cover
as shown on the right.
Selection of level and time
delay:
Upper knob:
Setting of upper level:
-10 to +100% of the range.
Centre knob:
Setting of lower level:
-100 to +10% of the range.
Lower knob:
Setting of delay on alarm
time: 0.1 to 30 s.
Function/Range/Level and Time Delay Setting
Setpoint range
ON: 2 Hz
OFF: 10 Hz
Relay working mode
ON: Normally De-Energized
OFF: Normally Energized
Contact input
ON: Lacth function enable
OFF: Inhibit function enable
System frequency
ON: 60 Hz
OFF: 50 Hz
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