Kuhse KRV 86.11 User manual

Alfred Kuhse GmbH, D-21423 Winsen/Luhe, An der Kleinbahn 39
Phone [phone], Fax [phone], http://www.kuhse.de
Certificated ISO 9001 since 1995
This service instruction contains information for design engineers, commissioning
and maintenance staff.
PRECAUTION HINTS
¾All applicable regulations, especially those of VDE, are to be observed.
¾A faulty connection may cause permanent damage to the unit.
APPLICATION
By means of the rapid and more accurate control
characteristics, electronic speed controllers are
more often used for speed resp. load control of
diesel and gas engines. Varying the rated value of
the speed controller can carry out a speed regula-
tion. Normally a resistor, which will be adjusted
manually or, in case of automatic gear, by means of
a servomotor, acts as the reference value transmit-
ter and supplies the governor with an analogue
signal according to the desired speed. Units, which
are used for speed control or load adjustment as
frequency controllers or active load sharing units,
transmit control pulses with a duration depending
on the control deviation.
The electronic reference value transmitter KRV
replaces the function of the motor driven rated
value potentiometer and converts the speed or load
controlling pulses into an analogue signal which
works directly the regulator; fast and accurate
control characteristics will be obtained.
The advantage of the KRV against the former used
motor driven potentiometers is mainly the possibil-
ity to adjust the reacting speed of the controlling
system continuously and the adapting can be
optimised. Furthermore the KRV works wearing
free, so that wearing faults, which occur mainly by
use of potentiometers, are excluded.
DESIGN
The KRV will be delivered in a plastic casing with
clip-on fasteners. The terminals are situated on the
front of the unit. By means of a potentiometer at the
front the maximum current limit of the control
current may be adjusted in a range of 0-20 micro
amps. At the potentiometer the sensitivity, i.e. the
reaction speed, is adjustable.
FUNCTION
After connecting the supply voltage, the green LED
ONindicates the operative condition. The drive of
the unit will be made via the following input termi-
nals and is indicated by LEDs:
Terminal 5 = decreasing speed
Terminal 6 = increasing speed
Terminal 7 = enable contact
On opening the enable contact, the reference value
current, which operates the regulator on the engine,
will be immediately set to zero. By that, the engine
runs now with the governor adjusted idle speed. If
the speed shall be modified, the enable contact must
be closed. It must remain closed permanently. By
operating the contacts DECREASING SPEED or IN-
CREASING SPEED the current will be adjusted up to
its maximum value in the negative or in the positive
range. The duration of the speed control pulse
affects the value of the current. By means of the
potentiometer SENSITIVITY the reaction time of the
engine may be adapted to the control system addi-
tionally. The controlling time depends on the ad-
justed maximum outgoing current Imax and on the
adjusted sensitivity, see diagram 1. The maximum
tolerable control current in the range of 0 to 20
micro amps. can be limited by means of the second
S165000.02-E
May 2003
Replaces: February 1996
Service Manual
Reference Value Transmitter for
Electronic Speed Controllers
Type: KRV 86.11

S165000.02-E - 2 / 3 - 05/2003
potentiometer. This prevents an overload of the
engine.
The adjusted value depends on the installed regula-
tor and amounts in case of Heinzmann and Barber
Colman regulators approx. 4 to 5 micro amps. In
case of an open enable contact the control current
amounts 0 micro amp, herewith in general the idle
speed of the engine will be adjusted at the engine
regulator. In case of engine stop or tripping of the
generator circuit breaker, the enable contact can be
opened. Herewith the engine will be set automati-
cally to its idle speed.
ADJUSTING AND COMMISSIONING INSTRUCTIONS
1. Check, if the unit is connected according to
wiring diagram and if shielded cables had been
laid. The cables must be laid twisted, the shield
must be connected to earth at the KRV only, it
must remain unconnected at the engine regula-
tor.
2. Open enable contact, connect measuring
instrument with a range of 0 to 20 micro amps
additional to terminals 8 and 9 and connect
supply voltage to terminals 1 and 2. The meas-
uring instrument must indicate 0 micro amps.
3. Start of the engine according to manufacturers
instruction and adjustment of the installed en-
gine regulator to the idle speed.
4. Basic adjustment as follows: Adjust the poten-
tiometer Imax to the value 5 micro amps, the po-
tentiometer for sensitivity to step 5, connect
the enable contact, increase the speed by a con-
tinuous signal on terminal 6. Observe speed or
frequency meter and ammeter. At reaching of
the adjusted max. output current, the idle speed
should be approx. 2% higher than the rated
speed. In case of a higher value Imax must be
reduced, in case of lower value it must be in-
creased accordingly.
5. Test by opening and closing of the enable
contact, whether the desired speed alteration
occurs.
6. Bring the speed to idle speed by opening the
enable contact. Synchronize the genset to other
gensets or to the mains and check, whether the
rated power of the genset will be reached with
the adjusted Imax. If the rated power will be
reached on a current value, which is below Imax
the Imax value must be limited to this value, in
case of not reaching the rated power, Imax is to
increase accordingly.
7. If the control speed is too slow, the sensitivity
must be increased (turn potentiometer to the
right) or decreased in case of too fast acting
(turn potentiometer to the left).
8. In case of oscillating, the regulator must be
disconnected by opening the terminals 8 and 9.
Check, if the oscillation arises from the regula-
tor or from the gas mixture. Load oscillations
may be reduced by decreasing the sensitivity
(turn potentiometer to the left).
TECHNICAL DATA
Supply voltage: 20 to 33 V DC
Supply current: 80 mA
Control current: -20 up to +20 micro amps.
Sensitivity: Control time acc. to diagram 1 max.
200 sec. Alteration of the control time from 0
micro amps. up to the adjusted current value I max.
in case of connecting a continuous signal.
Input resistance of governor: 5 up to 30 kOhm.
Protective grade: IP 20.
Mounting arrangement: any
Weight: 0.5 kp
Temperature range: -20°C up to +55°C.
Order number: 2165000.02
Connecting wires must be shielded and twisted.
Connect the shield to ground at the KRV, leave
it open on the other end.

S165000.02-E - 3 / 3 - 05/2003
Outline drawing (dimensions in mm)
Connecting diagram
Diagram 1 Control time in relation to the output current Imax.
Example for Adjustment: Eg. sensitivity of step and adjusted I (max.)= 5 micro amps, the control time takes
approx. 50s from 0 to 5 micro amps and approx. 10 s from 0 to 1 micro amp by continuous signal
Released: 23.06.2003 Gae