NR
117
The following is life data under our HP2 relay load.
(Notes)
1. When inrush current occurs in the capacitor load circuit or incandescent lamp load circuit, reduce it to less than 5 A. Electrical life of "A uCo" contact
types is 10,000 operations in a 5 A inrush current circuit.
2. When 5 A to 10 A inrush current occurs in the capacitor load circuit or incandescent lamp load circuit, the use of power types is recommended.
Contact voltage Contact current Contact protection circuit Operating speed Expected life, min. op.
6 V DC 232 mA 0.2 µF + 1kΩ or diode 2 op./s 3×107
12 V DC 106 mA 0.2 µF + 1kΩ or diode 2 op./s 3×107
24 V DC 54 mA 0.1 µF + 1kΩ or diode 2 op./s 3×107
100 V DC 15 mA 0.1 µF + 1kΩ or diode 2 op./s 2×107
24 V DC 80 mA 0.2 µF + 1kΩ2 op./s 3×107
100 V DC 20 mA 0.1 µF + 1kΩ or varistor 2 op./s 2×107
200 V DC 10 mA 0.1 µF + 1kΩ2 op./s 2×107
2 coil latching types
A) The circuit at right is recommended
when using one coil for latching and the
other coil for reset.
NR relays are sensitive enough to be op-
erated by the discharge of energy accu-
mulated in the inner-coil capacitance. The
use of a diode of over 200 V breakdown
will prevent misoperation from this source.
In order to maintain the insulation be-
tween the two coils , connection of the ter-
minal No. 3 and No. 6 or the terminal No.
2 and No . 5 is recommended, as shown in
the right figure.
Rectifiers should be inserted in this circuit
when the nominal coil voltage of the NR
relay is more than 24 V DC.
B) No damage will occur to the coil of ei-
ther the one or two coil latching types
even if the operating voltage is as much
as 2 or 3 times the nominal coil voltage.
C) If separate pulses are applied to each
coil of the 2 coil latching types, the first
pulse will operate when the pulses are of
equal voltage. When voltages differ the
higher voltage will cause operation pro-
vided the voltage difference is greater
than the measured pick-up voltage. Volt-
age difference on the coils will reduce
contact pressure proportionately.
Continuous bias voltage after an operat-
ing pulse lowers contact pressure and vi-
bration resistance.
bias voltage
coil
coil
Ripple factor
Coils should be operated on pure DC.
Rectified AC may cause changes in the pick-up/drop-out characteristics because
of the ripple factor. Use of a capacitor in the circuit is recommended to keep the
ripple factor below 5%.
: relay
E min. E max. E mean DC component
Pulsating component
capacitor (ripple filter)
R
R
To calculate the ripple factor
Ripple factor (%) = × 100%
E max. = max. value of pulsating component
E min. = min. value of pulsating component
E mean - average value DC component
E max. – E min.
E mean
When designing NR relay circuits
Care should be taken when designing re-
lay circuits since the response of the relay
is so f ast that bouncing or chattering from
conventional relays in the circuit may
cause false operation.
When using long lead wires
When long wires (as long as 100 m or
more) are to be used, the use of resis-
tance (10 to 50 Ω) in series with the con-
tact is required in order to eliminate the
effect of the possible inrush current due to
the stray capacitance existing between
the two wires or between the wire and
ground.
Contact of NR relay
Lead wire
+
Energy accumulated in
static capacitance
(100 to 300 m)
10 to 50 Ω
(Equivalent circuit)