8. Caution and Matters
8-1 Warnings:
In a motor near the end its life, or under breakdown
conditions, short circuits can develop between commutator
segments. Uncontrolled voltage may then leak into the
power source circuit. Motors may overheat or fail if run
continuously with its rotor locked condition or under
excessive loads.
8-2
Destructive atmospheres: Do not use and store the
motor in the corrosive gas atmosphere (H²S, SO², NO², Cl²,
etc.), or substances that can emit toxic gases, such as
organic silicon, cyanide, formalin, or phenol compounds.
The motor may get serious damages.
8-3 Condensation: Condensation on the electrical
circuits can destroy the motor or control circuits.
Monitor the environment and undertake measures to prevent
condensation, such as installing condensation sensors to
cut power when necessary.
8-4 Be aware of the following factors and perform
necessary tests to check a motor’s ability to adopt with
your mechanism and applications: Motor life, electric
noise, mechanical noise, vibration, static-electrical
noise resistance, power-source noise resistance, drift of
rpm, electrical resonance between control circuit and
motor, mechanical resonance between subassembly and motor
malfunction due to motor noise, electrical magnetic
interference, malfunction due to magnetic flux leakage,
destruction due to lightning-related power surge,
grounding.
8-5 Some particular plastic materials can crack and fail
after exposure to motor bearing oil. Perform test the
motor in/on the subassembly to check the influence of the
oiled plastic parts.
8-6 Avoid connecting a serial resistor to the motor if at
all possible, as this can negatively affect reliability.
If this is unavoidable, keep resistance as low as possible
and test thoroughly for reliability before using.
8-7 When testing for UL, CSA or other safely standards,
apply for approval for the entire subassembly.
8-8 Do not store motors under conditions of extreme
temperatures or high humidity, or for longer than six
months even room conditions. When removing out of
packaging after storage, take precautions to prevent
condensation.
8-9 Connections: Complete
soldering operations within three seconds to prevent
damage to leads and terminals. Make sure that the
soldering tip does not exceed 350°C. Be gentle with
terminals; dents or pressure on them can lock up the
motor.
8-10 Please consults us in advance when design
considerations call for forcefully stalling the motor
using a short circuit at the terminal or reverse voltage.
Such operations can shorten product life.
