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.