Tango's Ultimate Hot Rod House

Members Login
Post Info TOPIC: GM cs130 info


Mod

Status: Offline
Posts: 1322
Date:
GM cs130 info


CS Series / 4-terminal Alternators

These days, the more common arrangement on CS series alternators is to find four terminals on the voltage regulator, plus the alternator output terminal, and possibly a dedicated grounding terminal (for an actual total of 5 or 6 terminals). These alternators can be wired with anything from 2 to 6 wires, as we shall see (see why I avoid using terms like "2-wire alternator", as it actually tells us almost nothing!)

Terminals

IMG_6640m_400.jpg

This is a CS-130 alternator with 4 terminals at the voltage regulator (the black plastic housing labelled "Wiring Terminals" in this pic) plus the alternator output terminal (labelled "BAT" on this model).

 
IMG_6635m_400.jpg

On these later-model alternators, the voltage regulator terminals are pins rather than spade terminals.

As such, you can't just use standard electrical connectors - you need the matching plug - see the section on plugs below.

 
IMG_6643m_400.jpg

On this model, the terminals are labelled P, L, F, and S.

Other models will also have four pins in a similar arrangement, but they may be labelled P, L, I, S.

The functions of the terminals are as follows:

Terminal Label

Delco-Remy Name

Function

Connects to:

Notes

P

Phase (Relay)

Drives external device

Electric Tachometer or hour meter. (optional)

The "P" terminal is connected to the stator, and may be connected externally to drive a tachometer, hourmeter, or other device. Optional.

L

Indicator Lamp

Warning Lamp

Alt warning lamp

 

F

External Field Monitor

Used to externally monitor the rotor’s magnetic field.

External Device (optional)

The "F" terminal is connected internally to field positive, and may be used for diagnostics.

I

Ignition

Field Current Supply

Switched Ignition 12v+ (excitor wire)

Used to excite alternator, with or without a resistor between switch and terminal “I”, either a) in absence of an alternator warning lamp in the vehicle or b) as a backup (redundant) method of exciting the alternator.

S

Remote Sense

Voltage Sensing

Main Power Distribution Terminal

The "S" terminal may be connected externally to a voltage, such as the main power distribution point, to sense the voltage to be controlled.

B or Bat

Output Terminal

Alternator Output

Battery / Main Power Distribution

 

Notes: -

  • Alternator will have either an “F” terminal or an “I” terminal, but not both.
  • If the alternator has an “F” terminal (i.e. no "I" terminal):
    • It must be excited by the L terminal.
    • When exciting via the L terminal, there must be some resistance in the circuit (bulb and/or resistor) or a short circuit will be created.
    • If no alternator warning lamp is desired, a 50 Ohm resistor is used.
    • If an alternator warning lamp is used, a resistor should still be used, in parallel with the lamp. This is so that the bulb burning out does not prevent current flow and therefore alternator excitation. The resistor should be equivalent to a 3-4 watt bulb. Using Ohms law, we can use the Electrical Wheel of Doom from Part 1 to calculate the required value of the resistor as R = V^2 / Watts. In this case R = (14v*14v) / 4W = 49 Ohms. So a 50 Ohm resistor will do.
  • If the alternator has an “I” terminal:
    •  You can use this I terminal to excite the alternator, whether or not you are using an alternator warning lamp (i.e. whether or not anything is connected to terminal L).
    • Terminal “I” has a built-in internal resistor to prevent a short circuit when connected to the excitor wire. Therefore, you can connect the ignition switch to terminal “I” using an excitor wire with or without a resistor in series.
    • If you do not have or do not wish to install an alternator warning lamp, you can excite the alternator by connecting the ignition switch to terminal “I” using an excitor wire with or without a resistor in series.
    • If you do have an alternator warning lamp connected to terminal “L”, you can still connect the the ignition switch to terminal “I” using an excitor wire with or without a resistor in series as a backup method of exciting the alternator. This is good practice as this type of redundancy enhances reliability.

Wiring

It should now be obvious how to wire a CS-series / 4-terminal alternator, but just to summarize:

PLFS-type

Mandatory connections:

1) Connect the alternator output terminal (B or Bat) to the electrical system's main distribution point (bus bar, junction, etc.) Less optimal alternatives that will work include connecting it to the battery + terminal or a terminal on the starter motor that also connects to the battery + terminal.

2) Connect the L terminal to a source of switched ignition power through an indicator lamp wired in series. Also connect a 50 Ohm resistor in parallel with the indicator lamp so that if the bulb burns out, the alternator will still be excited.

3) Ensure there is a good ground connection between the bare alternator case, the mounting bracketry and the engine block/heads and/or install a dedicated ground wire from the engine block to the alternator's ground terminal (if it has one).

Crucial connections:

4) Strictly speaking, the alternator will work with only the three wiring connections listed above, but I consider it crucial for good performance that you also wire up the remote voltage sensing terminal. To do this, connect the S terminal to the vehicle electrical system's main power distribution point (bus bar, main switch, fuse panel, etc.). If the S remote voltage sensing terminal is not connected, the voltage regulator will revert to internal sensing of the alternator output terminal voltage - with all the limitations that brings. You will see some alternators wired with a short jumper wire from the S terminal directly to the battery connection at the back of the alternators, but this is neither the proper method for remote voltage sensing nor necessary for internal sensing - do it properly or leave it out.

Optional connections:

5) If you have an external device such as a tachometer, hourmeter, or other device, it may be connected to terminal P. Connect the device in the manner specified by the manufacturer of the device.

This is a diagram of such a CS-series, PLFS alternator wired using terminals L, S, and BAT.

PLFS.jpg

PLIS-type

Mandatory connections:

1) Connect the alternator output terminal (B or Bat) to the electrical system's main distribution point (bus bar, junction, etc.) Less optimal alternatives that will work include connecting it to the battery + terminal or a terminal on the starter motor that also connects to the battery + terminal.

2) Connect the L terminal to a source of switched ignition power through an indicator lamp wired in series. Also connect a 50 Ohm resistor in parallel with the indicator lamp so that if the bulb burns out, the alternator will still be excited.

3) Connect the I terminal to a source of switched ignition power through a 50 Ohm resistor wired in series.

3) Ensure there is a good ground connection between the bare alternator case, the mounting bracketry and the engine block/heads and/or install a dedicated ground wire from the engine block to the alternator's ground terminal (if it has one).

Crucial connections:

4) Strictly speaking, the alternator will work with only the three wiring connections listed above, but I consider it crucial for good performance that you also wire up the remote voltage sensing terminal. To do this, connect the S terminal to the vehicle electrical system's main power distribution point (bus bar, main switch, fuse panel, etc.). If the S remote voltage sensing terminal is not connected, the voltage regulator will revert to internal sensing of the alternator output terminal voltage - with all the limitations that brings. You will see some alternators wired with a short jumper wire from the S terminal directly to the battery connection at the back of the alternators, but this is neither the proper method for remote voltage sensing nor necessary for internal sensing - do it properly or leave it out.

Optional connections:

5) If you have an external device such as a tachometer, hourmeter, or other device, it may be connected to terminal P. Connect the device in the manner specified by the manufacturer of the device.

This is a diagram of such a CS-series, PLIS alternator wired using terminals L, S, I, and BAT.

PLIS.jpg

Plugs

To plug the wires into a CS-series alternator you need the factory-style plug. If you can scavenge one from a donor vehicle, great. If not, they are available separately from a number of sources, such as:

For CS-121, CS-130, and CS-144 alternators you can use either part number 46-1803 from WAI Global Industries, (www.waiglobal.com) pictured below:

46-1803.jpg

or

part number C120 from Quick Start Alternators (www.alternatorparts.com), pictured below:

C120.jpg

For CS-130D alternators you can use either part number 46-1810 from WAI Global Industries, (www.waiglobal.com) pictured below:

46-1810.jpg

or

part number C130D from Quick Start Alternators (www.alternatorparts.com), pictured below:

C130D.jpg



__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard