Rockwell Automation RELIANCE ELECTRIC DC3N Series User manual

DC3N Non-Regenerative DC Drive
User Guide
1/4 to 2 HP, 115/230 VAC
Instruction Manual D2-3452-4
M/N DC3N-12D-00-010-AI
M/N DC3N-12D-4X-010-AI

Corcom is a trademark of CII Technologies.
Reliance is a trademark of Rockwell Automation.
© 2004 Rockwell International Corporation All rights reserved
The information in this manual is subject to change without
notice.
Throughout this manual, the following notes are used to alert
you to safety considerations:
ATTENTION: Identifies information about practices or
circumstances that can lead to personal injury or death,
property damage, or economic loss.

IMPORTANT: Identifies information that is critical for successful
application and understanding of the product.

i
ATTENTION: Only qualified personnel familiar with
the construction and operation of this equipment and
the hazards involved should install, adjust, operate,
and/or service this equipment. Read and understand
this instruction manual in its entirety before
proceeding. Failure to observe this precaution could
result in severe bodily injury or loss of life.
ATTENTION: The user is responsible for conforming
with all applicable local and national codes. Failure to
observe this precaution could result in severe bodily
injury or loss of life.
ATTENTION: The control circuit is at line potential
when the drive is energized. Use a non-metallic
screwdriver when making adjustments to the circuit
board potentiometers. Exercise extreme caution as
hazardous voltage exists. Failure to observe these
precautions could result in severe bodily injury or loss
of life.
ATTENTION: It is possible for a drive to run at full
speed as a result of a component failure. Please
ensure that a master switch has been placed in the
AC line to stop the drive in an emergency.
ATTENTION: Reduce the chance of an electrical fire,
shock, or explosion by proper grounding, over-current
protection, thermal protection and enclosure. Follow
sound maintenance procedures.


ii Safety Warnings
ATTENTION: Starting and stopping with the start/stop
terminals does not disconnect AC power in the stop
position. A hardwired AC power disconnection switch
must be mounted between the AC source and
terminals L I and L2. This is required, as the DC drive
does not have an armature loop contactor. A single
fault like a power device short may cause motor
rotation when in the stop mode. The user is
responsible for assuring safe conditions for operating
personnel by providing suitable guards, audio or
visual alarms, or other devices. Failure to observe
these precautions could result in bodily injury.
ATTENTION: This Drive contains ESD (Electric Static
Discharge) sensitive parts and assemblies, Static
control precautions are required when installing,
testing, servicing, or repairing this assembly. Failure to
observe these precautions could result in damage to,
or destruction of, the equipment.


Specifications 1
Dimensions and Layout 4
Installation 7
Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Shielding guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Chassis drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Isolation transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Heat sinking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Fusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Line fusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Speed adjust potentiometer . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Alternate speed adjust potentiometer connections . . . . . . . . .15
Cage-clamp terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Power input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Field output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
START/STOP pushbuttons . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Tachometer feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Voltage or current follower . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Enclosed drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Heat sinking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Line fusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Power input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Contents
iii

Field output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Tachometer feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Voltage or current follower . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Slide switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
LINE VOLTAGE (SW501 and SW502) . . . . . . . . . . . . . . . . . . . .33
MOTOR (SW503) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
SIGNAL (SW504) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
FEEDBACK (SW505) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Operation 36
Before applying power (all models) . . . . . . . . . . . . . . . . . . . . . . . . .37
Drive operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Chassis drive operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
POWER ON start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Pushbutton start/stop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Alternate Starting and Stopping Methods . . . . . . . . . . . . . . . . . .41
Minimum speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Dynamic braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Dynamic brake resistor value . . . . . . . . . . . . . . . . . . . . . . . .43
Enclosed drive operating modes . . . . . . . . . . . . . . . . . . . . . . . . .45
Manual mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Auto mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Enclosed drive operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
To run the motor: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
To stop the motor: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Calibration 48
Drive Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
MIN SPD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
MAX SPD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
CURRENT LIMIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
IR COMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Approximate IR COMP calibration: . . . . . . . . . . . . . . . . . . . .55
ACCEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
iv Table of Contents

DECEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
TACH VOLTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
Application Notes 60
Multiple fixed speeds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Adjustable speeds using potentiometers in series . . . . . . . . . . . . .61
Independent adjustable speeds . . . . . . . . . . . . . . . . . . . . . . . . . . .62
Reversing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
RUN/JOG switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Troubleshooting 67
Before troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
Diagnostic LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Terminal descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
Chassis drive terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
Enclosed drive terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
CE Compliance 78
Exhibit “A” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
Armature Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
vTable of Contents
Tables
Table 1. Recommended Line Fuse Sizes . . . . . . . . . . . . . . . . . . . . . .13
Table 2. Field Output Connections . . . . . . . . . . . . . . . . . . . . . . . . . .20
Table 3. Field Output Connections . . . . . . . . . . . . . . . . . . . . . . . . . .29
Table 4. Minimum Recommended Dynamic Brake Resistor Values . .44
Table 5. Corcom® Filters www.corcom.com . . . . . . . . . . . . . . . . .79
Table 6. Armature Filters www.minarikcorp.com . . . . . . . . . . . . . .80

Figure 1. DC3N-12D-00-010-AI Dimensions . . . . . . . . . . . . . . . . . . . .4
Figure 2. DC3N-12D-4X-010-AI Dimensions . . . . . . . . . . . . . . . . . . . .5
Figure 3. PC Board Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Figure 4. Speed Adjust Potentiometer . . . . . . . . . . . . . . . . . . . . . . . .14
Figure 5. Cage-Clamp Terminal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Figure 6. DC3N-12D-00-010-AI Drive Connections . . . . . . . . . . . . . .23
Figure 7. DC3N-12D-00-010-AI Drive
Signal Follower Connection . . . . . . . . . . . . . . . . . . . . . . . .24
Figure 8. DC3N-12D-4X-010-AI Drive Connections . . . . . . . . . . . . . .31
Figure 9. Slide Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Figure 10. Run/Decelerate to Minimum Speed Switch . . . . . . . . . . . .42
Figure 11. Dynamic Brake Connection . . . . . . . . . . . . . . . . . . . . . . . .44
Figure 12. Calibration Trimpot Layout . . . . . . . . . . . . . . . . . . . . . . . .49
Figure 13. Typical CURRENT LIMIT
and IR COMP Settings for DC3N drive
(actual settings may vary with each application) . . . . . . . .59
Figure 14. Multiple Fixed Speeds . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Figure 15. Adjustable Fixed Speeds Using
Potentiometers in Series . . . . . . . . . . . . . . . . . . . . . . . . . .61
Figure 16. Independent Adjustable Speeds . . . . . . . . . . . . . . . . . . . .62
Figure 17. Reversing Circuit Connection . . . . . . . . . . . . . . . . . . . . . .64
Figure 18. RUN/JOG Switch Connection to
Speed Adjust Potentiometer . . . . . . . . . . . . . . . . . . . . . . .66
Figure 19. Diagnostic LED Locations . . . . . . . . . . . . . . . . . . . . . . . . .68
Figure 20. DC3N Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
vi
Illustrations

Specifications
Max.
Armature HP Range HP Range
Current with115 VAC with 230 VAC
Model (Amps DC) Applied Applied
DC3N-12D-00-010-AI 10A 1/4 – 1 1/2 – 2
DC3N-12D-4X-010-AI 10A 1/4 – 1 1/2 – 2
Model Style
DC3N-12D-00-010-AI Open chassis
DC3N-12D-4X-010-AI NEMA 4X/12
AC Line Voltage 115 VAC or 230 V AC, 50 or 60 Hz, 1 Phase
Maximum Allowable Symmetrical AC Line Current 5000 amps
Maximum AC Line Distribution kVA
with 115 VAC Input 25 kVA
with 230 VAC Input 50 kVA
Armature Voltage
With 115 VAC Input 0 – 90 VDC
With 230 VAC Input 0 – 180 VDC
Field Voltage
115 VAC Input 50 VDC (F1 to L1); 100 VDC (F1 to F2)
230 VAC Input 100 VDC (F1 to L1); 200 VDC (F1 to F2)
Maximum Field Current 1 ADC
Adjustments and Application Data
Form Factor 1.37 at base speed
Service Factor 1
Maximum Speed Trimpot Range (% of rated input voltage) 0 to 90%
1

Minimum Speed Trimpot Range (% of rated input voltage) 0 to 50%
Torque Trimpot Maximum Setting (% of maximum current) 200%
IR Drop Compensation (% of rated armature voltage) 0 to 15%
Acceleration Time Range 0.5 – 10 seconds
Deceleration Time Range 0.5 – 10 seconds
Analog Input Signal Range (S1 to S2) 0 – 10 VDC or 4 – 20 mADC
Input Impedance (S1 to S2) >100 KOHMS
Speed Regulation (% of base speed with 95% load change)
With Armature Feedback 1% or better
With Tachometer Feedback 0.1%
Speed Range 60:1
Tachometer Feedback Voltage Range 7 – 50 VDC per 1000 RPM
Maximum Current Load 150% for 1 minute
Safety Certification UL Listed Component
cUL Listed Component
CE Approved Component
Weight 2.1 lbs (953g)
Service Conditions
Maximum Allowable Elevation3300 ft (1000 m) max without derating*
Vibration 0.5G max. (0–50 Hz); 0.1G max. (>50 Hz)
Ambient Temperature Range
Chassis Drives 10°C – 55°C
Enclosed Drives 10ºC – 45ºC
Non-condensing Relative Humidity 0% to 95%
* Derate the current by 1% for every 300 ft (90m) above 3300 ft., up to 10,000 ft. (3000m)
2 Specifications

Drive Ratings DC Motor Motor
Rated DC Armature Field Field
Motor AC Line Input Armature Current Voltage Current
HP Amps KVA Voltage (Amps) (Amps)
1/4 4.5 0.5 90 2.7 50 1
4.5 0.5 90 2.7 100 1
1/3 5.9 0.7 90 3.5 50 1
5.9 0.7 90 3.5 100 1
1/2 7.8 0.9 90 5 50 1
3.7 0.8 180 2.5 100 1
3.7 0.8 180 2.5 200 1
3/4 10.6 1.2 90 7.6 50 1
5.6 1.3 180 3.8 100 1
5.6 1.3 180 3.8 200 1
1 13 1.5 90 10 50 1
7 1.6 180 5 100 1
7 1.6 180 5 200 1
1.5 -- -- -- -- -- --
10.1 2.3 180 7 100 1
10.1 2.3 180 7 200 1
2------ ------
12 2.8 180 9.2 100 1
12 2.8 180 9.2 200 1
Efficiency (at maximum horsepower output) 92%
3
Specifications

4
Dimensions and Layout
4.46 [113]
1.80 [46]
6.90 [175]
6.30 [160]
3.00 [76]
0.76 [19]
0.98 [25]
0.77 [19]
SIX (6) MOUNTING SLOTS
0.19 [5] WIDE x 0.30 [8] DEEP
ALL DIMENSIONS IN INCHES [MILLIMETERS]
Figure 1. DC3N-12D-00-010-AI Dimensions

5Dimensions
0
.22
[
6
]
6.90
[
175
]
6.30
[
160
]
9
.
80
[
249
]
1
0
.22
[
260
]
1.45
[
37
]
1.50
[
38
]
1.50
[
38
]
1.4
0
[36
]
7
.
00
[
178
]
0
.1
2
[
3
]
2.
31
[
59
]
4.7
8
[
121
]
5
.
5
1
[
140
]
THREE 0.88 [22] KNOCKOUTS
ALL DIMENSIONS IN INCHES [MILLIMETERS]
Figure 2. DC3N-12D-4X-010-AI Dimensions

6Dimensions and Layout
D
E
C
EL
MO
T
OR
S
W
503
A2
R
501
A1
F2
F1
R
C50
1
MAX
P
501
S
I
G
S
W
50
4
K50
1
IC50
1
+
C50
2
IC50
2
+
C503
P
502
B1
S1
S2
MIN
+
C50
4
ACC
EL
L1
L2
(
230
)
L2
(
115
)
TB
501
R502
FU501
F
1
FU502
F
D50
1
D50
2
D503
C50
1
P505
P506
T
A
C
H
ARM
S
W
505
T1
T2
VO
LT
S
T
A
C
H
C506
+
FB
IC505
IC50
4
T50
1
+
CU
RRENT
I
L
50
1
LIMIT
SC
R
50
2
IL502
I
R
CO
MP
B1
B
1B1
B1
S1
S
1S1
S1
S2
S2
S2
S2
T2
T
2T2
T2
T1
T
1T1
T1
A
C
LIN
E
F
US
E
S
(
FU501-FU502
)
LINE V
O
LTA
GE
S
ELE
C
T
O
R
S
WIT
C
HE
S
CU
RRENT LIMI
T
LED
(
IL501
)
P
O
WER LE
D
(
IL502
)
A
C
LINE V
O
LTA
GE
TERMINAL BL
OC
K
S
FIELD
TERMINAL BL
OC
K
S
ARMAT
U
R
E
TERMINAL BL
OC
K
S
ARMAT
U
RE V
O
LTA
GE
S
ELE
C
T
O
R
S
WIT
CH
CU
RRENT
/
V
O
LTA
GE
S
I
G
NAL
S
ELE
C
T
OR
S
WIT
CH
1
0
-T
U
RN MAXIM
UM
AND MINIM
U
M
S
PEE
D
TRIMMER P
O
TENTI
O
METER
S
S
PEED AD
JUS
T P
O
TENTI
O
METE
R
TERMINAL BL
OC
K
S
S
TART
/S
T
OP
TERMINAL BL
OC
K
S
TA
C
H
OG
ENERAT
OR
TERMINAL BL
OC
K
S
TA
C
H
OG
ENERAT
O
R V
O
LTA
GE
TRIMMER P
O
TENTI
O
METE
R
FEEDBA
C
K
S
ELE
C
T
OR
SWITCH
(
SW505
)
IR
CO
M
P
TRIMMER P
O
TENTI
O
METE
R
CU
RRENT LIMI
T
TRIMMER P
O
TENTI
O
METE
R
A
CC
EL AND DE
C
E
L
TRIMMER P
O
TENTI
O
METER
S
(
SW501, SW502
)
(
SW503
)
(
SW504
)
(
P501, P502
)
(
P505
)
(
P506
)
(
P503, P504
)
(
P507
)
Figure 3. PC Board Layout

7
Installation
ATTENTION: Only qualified technical personnel,
familiar with the construction and operation of this
equipment and the hazards involved, should install,
adjust, operate and/or service this equipment. Read
and understand this instruction manual in its entirety
before proceeding. Failure to observe this
precaution could result in severe bodily injury or loss
of life.
ATTENTION: This equipment is at line voltage when
AC power is connected. Disconnect and lockout all
ungrounded conductors of the AC power line before
working on the unit. Failure to observe this
precaution could result in severe bodily injury or loss
of life.
ATTENTION: The user is responsible for conforming
with all applicable local and national codes. Failure
to observe this precaution could result in severe
bodily injury or loss of life.


8 Installation
ATTENTION: Circuit potentials are at 115 or 230 VAC
above ground. To prevent the risk of injury or fatality,
avoid direct contact with the printed circuit board or
with circuit elements. Use a non-metallic screwdriver
for the calibration trimpots.
ATTENTION: Do not disconnect any of the motor
leads from the drive unless power is removed or the
drive is disabled. Opening any one motor lead may
destroy the drive.

Use 18-24 AWG wire for speed adjust potentiometer wiring.
Use 14–16 AWG wire for AC line (L1, L2) and motor (A1
and A2) wiring.
Shielding guidelines
ATTENTION: If it is not practical to shield power
conductors, Reliance Electric recommends shielding all
logic-level leads. If shielding logic leads is not
practical, use twisted-pair control wiring to minimize
induced electrical noise.

Wiring

9Installation
*Reliance Electric considers this an unfavorable condition and does
not recommend bundling power and logic leads for any length.
ATTENTION: Under no circumstances should power
and logic leads be bundled together. Induced voltage
can cause unpredictable behavior any electronic
device, including motor controls.

As a general rule, Reliance Electric recommends shielding
of all conductors if:
1) wire lengths exceed 4 inches and power and logic leads
must be bundled together*; or
2) radiated and/or conducted noise must be minimized due
to concerns about immunity or general compliance (CE,
FCC, etc.)
It may be necessary to earth ground the shielded cable. If
noise is produced by devices other than the drive, ground
the shield at the drive end. If noise is generated by a
device on the drive, ground the shield at the end away from
the drive. Do not ground both ends of the shield.
If the device continues to pick up noise after grounding the
shield, it may be necessary to add AC line filtering devices,
or to mount the drive in a less noisy environment.

10 Installation
Mounting
Protect the drive from dirt, moisture, and accidental contact.
Provide sufficient room for access to the terminal block and
calibration trimpots.
Mount the drive away from other heat sources. Operate the
drive within the specified ambient operating temperature
range.
Prevent loose connections by avoiding excessive vibration
of the drive.
Mount the drive with its board in either a horizontal or
vertical plane. Four 0.19 inch (5 mm) wide slots in the
chassis accept #8 pan head screws.
ATTENTION: This drive contains ESD (Electric Static
Discharge) sensitive parts and assemblies. Static
control precautions are required when installing,
testing, servicing, or repairing this assembly. Failure to
observe these precautions could result in damage to,
or destruction of, the equipment.
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Chassis drive

The chassis units do not have to be earth grounded. If you
choose to ground the chassis, use a star washer beneath
the head of at least one of the mounting screws to
penetrate the anodized chassis surface and to reach bare
metal.
Isolation transformer
11Installation
ATTENTION: Distribution system capacity above the
maximum recommended system KVA requires the use
of an isolation transformer, a line reactor, or other
means of adding similar impedance to the drive power
input. Failure to observe these precautions could
result in damage to, or destruction of, the equipment.
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Input isolation transformers might be needed to help
eliminate the following:
• Damaging line voltage transients from reaching the drive.
• Line noise from the drive back to the incoming power
source.
• Damaging currents that could develop if a point inside
the drive becomes grounded.

12 Installation
ATTENTION: Most code requires that upstream branch
protection be provided to protect input power wiring.
Failure to observe this precaution could result in severe
bodily injury or loss of life.
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Observe the following guidelines when installing an isolation
transformer:
· A power disconnecting device must be installed between
the power line and primary of the transformer.
· If the power disconnecting device is a circuit breaker, the
circuit breaker trip rating must be coordinated with the
in-rush current (10-12 times full load current) of the
transformer.
Heat sinking
This DC3 drive model contains sufficient heat sinking in its
original configuration. No additional heat sinking is
necessary when installed in accordance with the guidelines
specified in this instruction manual. The chassis plate acts
as the thermal heatsink.
Fusing
Install the required, user-supplied branch circuit protection
fuses according to the applicable local, national, and
international codes (e.g., NEC/CEQ).