Installation, Operation and Service Manual
LKP Series 4 Channel OEM
© 2019 DynAmp, LLC
Page 16
041593O
CAUTION
Avoid operating the unit for an extended time with any channel output over 35 V. This
will permanently damage the system. For voltages over 35 V, consult the factory.
E.) If any of the channel readings do indicate trouble, refer to Theory of Operations and
Maintenance & Spare Parts sections and resolve the problem; then proceed with "Magnetic
Centering".
Note 1.
Low Readings: A very low amplifier output voltage may be normal for certain
channels; however, ripple can be as high as 3 V on a non-operating (full-off) channel.
Thus, a very low reading (i.e., 1 V to 3 V, should be suspected as a possible problem;
subsequent head movement or other magnetic change may show that the channel is
operating properly.
Note 2.
High Readings: The maximum allowable channel output of 35 V relates to the
maximum heat dissipation that the channel can safely handle. A reading of 25 V to 35 V
makes a change in head position highly desirable. A reading exceeding 35V makes a
head position change necessary. A reading of 70-75 V indicates a full-on channel
condition or a blown channel fuse, and requires immediate action to resolve the
problem. A reading of 35-38 V when immediately adjacent channels are significantly
different may indicate that one of the two SCRs in the channel has failed.
F.) Read and record the voltage drop across the burden circuit, as indicated in the table. There
should be no more than 15 volts when all systems are at maximum operating levels.
Figure 4.3
Measuring Head Orientation
1. Bus current (conventional current not electron flow) must flow into rear face, which is
identified by red dots on LKP-6 and LKP-12 Measuring Heads.
2. Current direction arrows on LKP-15 and LKP-30 Measuring Heads identify bus current
direction.
3. Channel No. 1 is always located on cable exit side.
