# DC motor

#### aGpLT

Joined Jan 21, 2010
128
Hello everyone, i want to ask about this dc motor - YRS - 380S SHEN LONG 2.4VDC. I searched for information about it but couldnt find it. I need to properly choose components for DC motor controller but i cant do that without any information. Sorry for bad language.

#### Bernard

Joined Aug 7, 2008
5,601
Do you have a meter capable of measuring up to 5 amps? Using two 1.5 V batteries in series & in series with meter & motor, on highest scale measure current, turn off and lower scale if in range, re check. Check with no load , pinch shaft ' till just above stall, record current. Your speed control needs to handle highest current recorded.

#### aGpLT

Joined Jan 21, 2010
128
Do you have a meter capable of measuring up to 5 amps? Using two 1.5 V batteries in series & in series with meter & motor, on highest scale measure current, turn off and lower scale if in range, re check. Check with no load , pinch shaft ' till just above stall, record current. Your speed control needs to handle highest current recorded.
Yeah i have cheap one max 10A. For this project i will use power supply from computer with 5v output, so i think i need some stabilizer for circuit to get best of these motors ? Itried with this pwr supply to scale how much motor require drain without load. So i measured my pwr supply (15 amps) when i connected motor and measured again (14 amps) its without load, when i tryed to put some load on motor, and measured again (13,5amps) But i think this information propably is incorrect becouse of my meter. I will try again with two 2x1.5V and reedit this post :]

#### Bernard

Joined Aug 7, 2008
5,601
How did you measure 15A with 10A meter[ Ouch ]. Try some resistance in series with motor on +5 V, starting around 30 Ω, measure motor V , adj resistor values untill motor V near 2.4V.

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#### aGpLT

Joined Jan 21, 2010
128
How did you measure 15A with 10A meter[ Ouch ]. Try some resistance in series with motor on +5 V, starting around 30 Ω, measure motor V , adj resistor values untill motor V near 2.4V.

Hmhm i needed 3x330kohm resistors in series to get to 2.4V.... is it something i am doing bad or what ? ;] rats i feel so uneasy... so lame... :[[

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#### Bernard

Joined Aug 7, 2008
5,601
Ω = ohm, I do not think all of our gears are meshing.

#### aGpLT

Joined Jan 21, 2010
128
Ω = ohm, I do not think all of our gears are meshing.
yeah i know what ohm mean ;] but when i tryed 30 ohm resistence when voltage is 5V only when i use 3x330Kohm it drops to 2.4v

#### Bernard

Joined Aug 7, 2008
5,601
Was the motor running when measurements were taken with 1M ohm in series? Sounds like brushes sitting on gap between commutator segments and just measuring leakage; if it's running then WOW, near perpetual motion.

#### aGpLT

Joined Jan 21, 2010
128
Was the motor running when measurements were taken with 1M ohm in series? Sounds like brushes sitting on gap between commutator segments and just measuring leakage; if it's running then WOW, near perpetual motion.
nope it dont. when i try with 30 Ohm its still dont run :]

#### Bernard

Joined Aug 7, 2008
5,601
Keep dropping resistor value untill motor duns at normal speed, then measure current.