Cole Parmer CG-500 User manual

1300-87052-1M, REV 6
CG-500 Freezer/Mill®
Cryogenic Grinder Designed for Milling Tough and Temperature Sensitive Samples
Operation Manual
For 115V (04500-42) and 230V (04577-94)

CG-500 Freezer/Mill
1300-87052-1M, REV 6 Cole-Parmer® Page 2 of 33
Copyright 2023 by Cole-Parmer®
All rights reserved. No part of the work may be reproduced or transmitted in any form or by any
means, electronic or mechanical; including photocopying and recording, except as may be
expressly permitted by the 1976 Copyright Act or in writing from the publisher. Requests for
permission should be addressed in writing to Cole-Parmer®, 65 Liberty Street, Metuchen, NJ
08840.
SPEX SamplePrep is now part of Cole-Parmer®.
The Cole-Parmer® CG-500 Freezer/Mill was formerly known as SPEX 6875D Freezer/Mill.
Over the years, we’ve acquired many high-quality and reputable brands. After many years
of continual growth, we realize our brands are all as brilliant as each other. Rather than
have a portfolio of complementary brands, we felt consolidating them under one world-
class brand name enabled us to offer a single and significant brand experience. Through
one brand we can speak in one voice through our team of experts who provide support in
product selection, usage and troubleshooting to empower laboratories to run efficiently
throughout the world.
Same Great Quality!
One World-Class Brand Name!

CG-500 Freezer/Mill
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TABLE OF CONTENTS
SECTION
DESCRIPTION
PAGE
1.0 Introduction ........................................................................................................................4
2.0 Specifications ......................................................................................................................5
3.0 Unpacking ...........................................................................................................................6
4.0 Setting Up............................................................................................................................7
4.1 Electrical Connection.........................................................................................................7
4.2 Power Switch and Controller ............................................................................................8
4.3 Liquid Nitrogen Connection………………………………………………………………………………………….9
4.4 Lid, Coil Assembly and Gate, LN Sensor ...........................................................................10
4.5 Grinding Vial Sizes, Adapters, and Vial Openers............................................................11
5.0 Touchscreen Display.........................................................................................................12
5.1 Logo Screen.......................................................................................................................12
5.2 Control Panel.....................................................................................................................13
5.3 Changing Settings..............................................................................................................17
5.4 Saved Protocols.................................................................................................................18
6.0 Operation..........................................................................................................................20
6.1 Standard Auto Fill………………………………………………………………………………………………………20
6.2 Manually Adding Liquid Nitrogen.....................................................................................21
6.3 Loading Vials into the Freezer/Mill...................................................................................24
6.4 Removing Vials from the Freezer/Mill..............................................................................24
6.5 Opening, Emptying, and Cleaning Freezer/Mill Vials.......................................................24
6.6 Checking the Liquid Nitrogen Level..................................................................................27
7.0 Run History........................................................................................................................27
8.0 System Settings…………………….…………………………………………………………………………………..28
9.0 Maintenance……………………………………………………………………………………………………………..28
10.0 Trouble-Shooting Guide....................................................................................................29
11.0 Warranty...........................................................................................................................31
11.1 Product Specifications ......................................................................................................31
11.2 To Arrange a Return Shipment.........................................................................................31
12.0 Instrument Disposal..........................................................................................................32
13.0 Contact Us.........................................................................................................................33

CG-500 Freezer/Mill
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1.0 INTRODUCTION
Cole-Parmer Freezer/Mills are laboratory mills that cool unconventional materials to cryogenic
temperatures and pulverize them to a powder form without thermal degradation. Our proven
technology uses a dual electromagnetic, grinding chamber that rapidly drives a steel impactor
back and forth against the two end plugs of the sample vial. Since the vial is securely closed the
integrity of its contents is maintained, hazardous or critical samples are easily controlled, and
cross-sample contamination is eliminated. The sample chemical composition is preserved as a
result of the vials being immersed in liquid nitrogen at cryogenic temperatures throughout the
grinding process. The CG-500 Freezer/Mill expands on this technology utilizing dual grinding
chambers and two additional precooling chambers for increased sample throughput. The CG-
500 Freezer/Mill has been re-engineered with a liquid nitrogen Auto Fill feature which comes
standard in every unit. The preference to Manual Fill the unit with liquid nitrogen is optional.
These unique aspects have made Cole-Parmer Freezer/Mills the most effective cryogenic mills
in the world. They are the “mills of first choice” for many abnormal materials, or samples
whose composition or structure cannot be ground using conventional grinding methods.
NOTE: Do not operate the CG-500 Freezer/Mill until you have read the Operating Manual and
are familiar with the controls and operation.
OPERATING CONDITIONS: Do not set up the CG-500 Freezer/Mill in an insulated or confined
space. The Freezer/Mill should be run on an open countertop, in ambient air, with
recommended maximum relative room humidity 70% from 5°C - 31°C (40°F - 88°F). If the entire
mill is chilled during operation, components such as the gas springs, controller, and display
screen can fail. This damage is not covered by the Freezer/Mill warranty. During operation,
water vapor in the air will condense on parts of the unit. For this reason, it is important not to
place any moisture-sensitive equipment near the Freezer/Mill.
VERY IMPORTANT: Liquid nitrogen(LN) not only makes samples brittle through severe chilling
and making them “grindable,” but it also cools the magnetic coils which power the CG-500
Freezer/Mill. If the unit is operated in the optional Manual Fill mode the liquid nitrogen level
should be visually checked during extended runs as well as topped off before every run.
Operating the unit without liquid nitrogen for a period of one minute will cause the coils to
become very hot and may sustain permanent damage. The CG-500 Freezer/Mill has an LN
sensor that will shut down the unit when the liquid nitrogen gets too low to cool the coils. The
Freezer/Mill warranty does not cover damage to the coils caused by operating the mill with
little or no liquid nitrogen. We recommend operating the unit in Auto Fill mode with LN Tank.
SAFETY: Liquid nitrogen (LN) can be hazardous. Its boiling point is -195.8°C (-320.4°F). When
working with liquid nitrogen directly or indirectly, the LN Tank valve or hose, or chilled
Freezer/Mill components, cryogenic gloves must be worn to protect hands. A face Shield is also
recommended to protect eyes from possible splashing. Wear the proper protection equipment
PPE).

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2.0 CG-500 FREEZER/MILL SPECIFICATIONS
Type of Mill: Dual Chamber Cryogenic impact mill
Controller: Touchscreen
Data Transfer: Dual USB Port (back of controller)
Grinding Mechanism: Steel impactor driven by magnetic coil
Coolant: Liquid nitrogen (LN)
Dimensions: 20 in. (50.8 cm) x 21½ in. (55 cm) x 25½ in. (64.77 cm)
Weight: (empty, without vial or coolant) approx. 78 lbs. (35.38 Kg)
Grinding Vials: One Large Vial (6801, 6803, 6871), one Mid-Size Vial (6881, 6883,
6885), one to four Small Vials (6751, 6761, 6771, 6781S) or one to
four Microvial set (6757). (Per Chamber)
Typical Vial Capacity: Small Vial:actual volume with impactor, approx. 25 ml. Typical
sample weights: 2 grams for biological samples, 1 gram for polymers.
Microvial Set:100 - 500 mg per individual Microvial, depending on
sample.
Mid-Size Vial:up to 5 times the sample capacity of Small Vial.
Large Vial:Approximately twice the sample capacity of Mid-Size Vial,
or up to 10 times that of Small Vial.
Actual performance of any vial/sample combination depends on
sample properties, cooling time, grinding time, desired outcome, etc.
Effective capacity for a given sample is determined by experiment.
Overfilling a vial greatly reduces its efficiency.
Typical Liquid Nitrogen 15-19 liters for initial cool-down and filling of the tub.
Consumption: 4-6 liters for each hour of operation. Actual liquid nitrogen
consumption can vary. A minimum 200L LN Tank is recommended.
Electrical Specifications: CE Approved. Available as 115V/60HZ or 230/50HZ.
Circuit Breaker: Same as ON/OFF Switch.
Power Cord: 115V/60HZ version: 3-prong grounded plug supplied.
230V/50HZ version: 2-prong European plug supplied.
Operator is responsible for supplying alternate line cord/plug.
Safety Features: Lid Interlock prevents mill from running if lid is not securely latched.
Liquid nitrogen sensor shuts down the mill if LN level is too low.
NOTE: The liquid nitrogen sensor can shut down the mill during a run if LN level is low.
The Freezer/Mill warranty does not cover damage to the magnetic coils caused by
operating the mill with little or no liquid nitrogen.

CG-500 Freezer/Mill
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3.0 UNPACKING
Inspect the exterior of the packing box and report any visible damage to the carrier. Remove all
packing documents from the exterior of the box, and save them for your records. Open the top
of the shipping box. Remove the packing material and accessories, and gently remove the CG-
500 Freezer/Mill. Visually check the mill for any damage that may have occurred during
shipping. Unlatch the lid and inspect the interior of the tub, ensuring that it is free of any
packing material. Check the packing list to see that there are no parts missing, and inspect the
accessories. We recommend storing the packaging materials in the event there is a need to
return the unit for warranty service or repairs.
Grinding vials must be purchased separately and are available in four sizes: large, mid-size,
small, and micro. An Accessory Package is available to match your choice of vials for each new
CG-500 Freezer/Mill. The 6870L for large vials, the 6870M for mid-size vials, the 6870S for
small vials or 6757 for microvials. The 6870S also includes a vial holder for running up to four
small vials per CG-500 grinding chamber. The full range of grinding vials and accessories for the
CG-500 Freezer/Mill is described in our catalog, The Freezer/Mill Accessory Manual, and at
www.Cole-Parmer.com.
Figure 1 –CG-500 Freezer/Mill, Front View
PRECOOLING CHAMBER
GAS SPRING
FRONT OF UNIT
GATE HANDLE
LATCH
CHAMBER 1
CHAMBER 2

CG-500 Freezer/Mill
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3.0 UNPACKING (Cont’d)
Figure 2 –CG-500 Freezer/Mill, Rear View
4.0 SETTING UP
The CG-500 Freezer/Mill weighs 78 pounds (35.38 Kg) empty. The lid opens from the front with
the lid latch in the center. The AC Input module and the ON/OFF switch (which also serves as a
circuit breaker) are on the back of the cabinet. The vent for the liquid nitrogen tub is on the
back of the cabinet where the vent hose assembly is attached. There are gas springs on both
sides of the cabinet to control the movement of the lid. The touchscreen, controller is affixed
to the top of the lid and linked to the unit by a RJ45 Ethernet cable connector. At the back of
the controller is a “dual” USB Port to download run data, or to upgrade software.
Caution:
4.1 Electrical Connection
Plug the electrical cord into the AC Inlet on the back of the Freezer/Mill cabinet, and then into a
standard 3-prong grounded electrical outlet. The 230V/50HZ CG-500 Freezer/Mill is supplied
with a standard European 2-prong plug with cord. For the 230V/50HZ version, make sure the
cord and plug conform to local electrical codes.
TOUCHSCREEN/CONTROLLER
[Dual USB PORT BACK OF CONTROLLER]
BACK OF UNIT
ON/OFF SWITCH (Circuit Breaker)
VENT HOSE
ASSEMBLY
AC INLET
AUTO FILL
Do not tip the Freezer/Mill on its side to drain liquid nitrogen
out of the tub. Damage can occur to the mill preventing it from
operating. In a well vented room, raise the lid to its full upright
position and allow the liquid nitrogen to evaporate.

CG-500 Freezer/Mill
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4.2 Power Switch and Controller
Electric power to the Freezer/Mill is controlled by a rocker switch on the inlet module. It is
marked with two numerical symbols (0 for OFF and l for ON). Press the “l” side of the switch to
turn the power ON, or press the “0”side of the switch to turn the power OFF. When power to
the mill is turned ON, the controller display will light up followed by a beep.
The controller is a touchscreen that can be activated by a fingertip or stylus. Run data is
transferred to other computer devices via USB Port, located in back of the controller. The CG-
500 Freezer/Mill can be programmed to operate Chamber 1 only, or Chamber 1 and Chamber 2
simultaneously through the control panel by successive screens which are described and
illustrated in Section 5.2.The programmable parameters include Cycles (number of grinding
periods), Precool Time (initial chilling of sample), Run Time (grinding period), Cool Time (time
between grinding periods), and Rate (speed of the impactor in cycles per second). The control
panel also displays a warning if the lid is not fully closed, or if there is not enough liquid
nitrogen in the tub.
The viewing angle of the controller on the CG-500 Freezer/Mill can be adjusted to minimize
glare. To adjust the viewing angle, simply grasp the back of the controller box and gently pull it
forward until the desired angle is reached, as shown in Figure 3. If it is necessary to send the
unit back to COLE-PARMER for service, be sure to return the controller to its horizontal position
before packing the unit for shipping.
Grasp controller from the rear and
gently pull forward to adjust viewing
angle from the horizontal position.
USB Port
(back of controller)
Figure 3 –Adjust the Viewing Angle of the Controller

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4.3 Liquid Nitrogen Connection
The CG-500 Freezer/Mill was re-engineered with an Auto Fill feature that comes standard with
every unit. The Auto Fill transfers liquid nitrogen to the tub during operation, making hand-
filling the LN tub optional. The Auto Fill mechanism includes a cryogenic valve linked to LN
sensors in the tub. When the LN Level is Low, the valve opens during Precool or Re-Cool stages
to let liquid nitrogen into the tub. The liquid nitrogen connection, as supplied also includes a
safety valve for the liquid nitrogen transfer hose.
Liquid nitrogen transfer hoses can vary with LN Tanks or LN lines and is therefore not included
with the Liquid Nitrogen Connection. Four-foot and six-foot transfer hoses of standard design
(part numbers 6906 and 6907) can be purchased separately from Cole-Parmer, or custom
transfer hoses can be designed specifically for the user. The liquid nitrogen inlet is a male 1/2
inch JIC fitting placed low on the right (facing) side of the Freezer/Mill, the outlet of the hose
requires a female CGA295 fitting. The 160 liter and 240 liter LN Tanks used by many of our
customers typically have a male 3/8 inch (9.5 mm) NPT outlet, COLE-PARMER transfer hoses
come with a matching female 3/8 inch NPT fitting. Excessively long transfer hoses are not
recommended.
LN Tanks come in two types, high-pressure and low-pressure. Some LN Tanks have valve
systems to switch from low pressure to high pressure. Always use a low-pressure liquid
nitrogen supply, with a delivery pressure of 20-22 psi.
Install the safety valve on the outlet of the LN Tank or LN line, with the gooseneck tilted up and
the valve outlet down (Figure 4). Then attach the LN transfer hose to the safety valve, and the
other end to the inlet on the CG-500 Freezer/Mill. The safety valve should be higher than the
LN inlet on the Freezer/Mill. The purpose of the safety valve is to provide an exit for liquid
nitrogen vapor in case the mill and LN Tank valves are both closed, and pressure builds up
inside the hose. Caution: When the lid is closed and latched, nitrogen vapor which vents from
the Freezer/Mill can displace the oxygen in a closed room and cause asphyxiation.
When installing the safety valve and transfer hose, use Teflon plumber’s tape on all threaded
fittings, and tighten the nuts with a wrench. If the fittings leak, tighten them further and/or use
more Teflon plumber’s tape.
Caution: Safety goggles should be worn at all times to protect eyes from accidental splashes
or liquid nitrogen vapor. Cryogenic gloves must be worn to protect hands.

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4.3 Liquid Nitrogen Connection (Cont’d)
4.4 Lid, Coil Assembly and Gate, LN Sensor
The lid of the CG-500 Freezer/Mill supports the coils (dual electromagnet assembly), two
precooling chambers, and grinding Chamber 1 and Chamber 2 enclosure. To open the lid, hold
the lid down with one hand, and with the other hand pull the upper end of the latch toward
you. Then pull the lower end of the latch to detach it from the cabinet. Release the lid and it
will raise up by the gas spring arms. The gas spring arms will keep the lid in the upright
position. The lid must be open for insertion and removal of vials.
A vial can be inserted into either precooling chambers, or Chamber 1 and Chamber 2 of the
assembly. The Gate keeps the vial(s) in place during grinding for Chambers 1 and 2 only. The
vials in the precooling chambers will remain secure and unaffected by the magnetic coils in
Chamber 1 or Chamber 2. Do not run the CG-500 Freezer/Mill without a loaded sample vial in
the grinding Chamber(s) that is active (programmed to grind).
The Gate (Figure 1) holds the vial(s) in Chambers 1 and 2 during grinding. To lock a vial in place,
turn Gate Handle to the left, and position it to pass through the slot in the open Gate. Now
close Gate and turn Gate Handle to the right against the Gate, then fold down Gate Handle to
Safety Valve
1/2” female JIC
connects to LN Tank or
LN line
1/2” female JIC
LN Transfer Hose
3/8” female NPT
3/8” male NPT
1/2” female JIC
1/2” male JIC
on CG-500
Swivel Joint
Adapter
Apply Teflon tape here
Figure 4 - Liquid Nitrogen Connection (included
with CG-500, except for LN Transfer Hose)