when wheel slip is detected. This is common when lifting or
transporting heavy loads, and under poor track conditions such as ice, snow or rain.
Real time detection and response to wheel slip problems routinely allows higher
adhesion coefficients for train dispatch. QTRAC 1000 also controls rail sanding, and
provides increased performance due to the tractive effort gained from the Wheel
Creep Control feature.
The QTRAC 1000 is currently available for most GM/EMD locomotives, and is
readily adaptable to others.
The QTRAC 1000 also:
Monitors diagnostics of all QTRAC 1000 inputs and outputs, including:

Some Contactor and Relay positions.

Traction Motor Currents (6 on SD units; 4 on F9 and GP units).
Records and stores Alarms (450 alarms):
Includes a snapshot of all Input/Output data at the time of the alarm occurrence.

In Alarm data mode, view the complete I/O data on the QTRAC 1000 Liquid
Crystal Display (LCD) at the time of the alarm occurrence.

Download Alarm data to an external computer and view it using the Q-Tron
Universal Analysis/Download Software (QUADS) program.
Monitors total:

Horsepower Hours.

Kilowatt Hours.

Hours.

Miles.
2
QTRAC 1000 Traction Control System
System Overview

The QTRAC 1000 Wheel Slip/Creep Control operates in both Power- and
Dynamic Braking mode. The QTRAC 1000 continually self-checks its memory
and internal circuits, and provides diagnostics information to aid while testing
and troubleshooting the system.

The QTRAC 1000 can be used with a computer interface to download and view
alarms that are recorded by the system when irregular Wheel Slip operations
occur.

Current transducers for each Traction Motor (TM) detect traction motor
irregularities such as pinion slip, and short or open circuits.

QTRAC 1000 module mounting hardware is available for Dash 2 and
non-Dash 2 locomotives.
System Performance
The QTRAC 1000 Traction Control system is an economical way to significantly
boost track adhesion and locomotive performance. The QTRAC 1000 controls wheel
slip/creep in power and dynamic brake operation by reducing excitation to the main
generator when wheel slip is detected in one of the axles. The result can be as high as
a 34% improvement in track adhesion under poor rail conditions.
Motor Protection
The QTRAC 1000 senses armature currents on all traction motors. By comparing
motor currents, the QTRAC 1000 provides open Traction Motor protection and
Pinion Slip protection.
If the average Traction Motor current exceeds 50 amps and the armature current of
one motor is 25 percent higher (or lower) than average current, a SLIP PINION alarm
is set. If this happens, Rate Control is set to zero and the Generator Field (GF) output
opens. After 3 seconds, the Generator Field output closes and the Rate Control ramps
up.
If average Traction Motor current is greater than 100 amps and armature current in a
motor is less than 50 amps, a TM OPEN alarm is set. If this happens, Rate Control is
set to zero and the Generator Field output opens. After 3 seconds, the Generator Field
output closes and the Rate Control ramps up.
By receiving the speed signals from all axles, the QTRAC 1000 can protect against
locked axles and axle overspeed. If average speed is higher than 3 MPH and one axle
is detected to be less than 1 MPH, an AXLE LOCKED alarm is displayed and Rate
Control is reduced. If an axle speed exceeds 73 MPH an OVERSPEED alarm is set
and Rate Control is reduced.
Traction motor temperature is calculated based on cooling air temperature, the
amount of cooling air, and traction motor current. If the temperature of the traction
motor exceeds 180°C, excitation is reduced to limit the traction motor current. This
prevents damage to the traction motor.

QTRAC 1000 Traction Control System
3
Wheel Slip/Creep Control
Wheel slip/creep control operates in both DB and Power. The speed based control
system utilizes 120 pulse per wheel revolution (PPR) speed signals from each axle
through the use of axle generators. The system controls wheel slip by monitoring
absolute acceleration of each axle. If an axle accelerates too quickly the main
generator excitation is reduced just enough to control the wheel slip, providing as
much tractive effort as rail conditions permit.
The current based control system monitors traction motor current transducers, main
generator voltage and current, and differential voltage modules. After analyzing these
signals, the QES III system adjusts system power to the traction motors.

The Wheel Slip/Creep Control system allows the wheels to creep at 12 MPH above
track speed. As wheel slip increases, main generator power decreases. Power to the
traction motors is cut quickly and then reapplied to just below the amperage level at
which the wheel slip occurred. The controlled power levels result in continuous
wheel creep to provide a significant increase in adhesion over conventionally
equipped locomotives.
Miscellaneous
Interface Panels are available for controlling main generator excitation or D32
equipped locomotives. 4
QTRAC 1000 Traction Control System
QTRAC 1000 Display Panel
The display panel provides access to the various functions performed by the QTRAC
1000. The QTRAC 1000 panel displays the data for diagnostics, operation of Speed
Control, and the self-tests. The display also provides the viewing screen for checking
Totals, viewing Alarm Data, and entering Setup Parameters.
The QTRAC 1000 display consists of a 4-line by 20-character alphanumeric Liquid
Crystal Display (LCD), and a 12-button keypad for selecting program functions and
inputting information. The QTRAC 1000 interfaces with the laptop computer using a
serial (RS-232) cable link. Figure 1 displays the layout of the QTRAC 1000.
3
2
1
MADE IN CANADA
CLR
0
ENT
RS-232
7
4
8
9
5
6
724013 04

Figure 1. QTRAC 1000 display panel