DC.

Pages 1 - - 60 - 61 - 62 - 63 - 64 - 65 - 66 - 67 - 68 - 69 - 70 - 71 - 72 - 73 - 74 - 75 - 76 - 77 - 78|||

MIL-DTL-17361G(SH)

APPENDIX A

b. The AQB-LL400 and AQB-L400 designs are not functionally equivalent with respect to interruption rating.

The AQB-L400 designs have an interruption rating of 150KA and the AQB-LL400 has an interruption rating of

100KA.

c. The AQB-LL400 and AQB-L400 designs are not functionally equivalent with respect to short-time pickup

ranges. Also, the two AQB-L400 designs are not functionally equivalent with respect to short-time pickup ranges.

The ranges are as follows:

AQB-LL400:

3600�5800 amps

AQB-L400QF:

650�1500 amps

AQB-L400QM:

1700�3200 amps

d. The AQB-LL400 and AQB-L400 designs are not functionally equivalent with respect to fixed

instantaneous pickup settings. Also, the two AQB-L400 designs are not functionally equivalent with respect to

fixed instantaneous pickup settings. The settings are as follows:

AQB-LL400:

6300 amps

AQB-L400QF:

1850 amps

AQB-L400QM:

3280 amps

A.3.4.4 Form, fit, and function replacement considerations (circuit breakers from different vendors). Note the

following:

a. Because of significant dimensional differences, the Cutler-Hammer AQB-LL400 and AQB-L400 cannot be

used as form and fit replacements for the SPD AQB-A400.

b. The Cutler-Hammer AQB-LL400 and AQB-L400 are smaller than the SPD AQB-LF400 and do not have a

fuse unit like the SPD AQB-LF400. To make them form and fit replacements for the SPD AQB-LF400, an adapter

kit supplied by Cutler-Hammer is required. The kit consists of modified line and load side interface connectors and

a close-out plate. The connectors allow the Cutler-Hammer AQB-LL400 and AQB-L400 to fit into the SPD AQB-

LF400 mounting base/block. The close-out plate covers the gap between the bottom of the Cutler-Hammer AQB-

LL400/L400 and the switchboard cover where the SPD AQB-LF400 fuse unit used to be.

c. Attachments (if applicable) and adjustable settings must be taken into consideration to make the Cutler-

Hammer circuit breakers functional equivalents to the SPD AQB-LF400. See A.3.4.5 for attachment information.

See A.3.8 and Table A-XV for guidance on how to set the Cutler-Hammer AQB-LL400 and AQB-L400 designs to

make them functional replacements for the SPD AQB-LF400 with respect to CCS and overcurrent protection.

A.3.4.5 Attachments. Attachments include motor operators, undervoltage releases, shunt trips and auxiliary

switches. Important aspects of attachments are ratings and number and type of leads or connectors exiting the

circuit breaker. These aspects can differ depending on which type of circuit breaker is involved. See A.3.3.5.1,

A.3.3.5.2, A.3.4.5.3, A.3.7, and Table A-III for more information on attachments.

A.3.4.5.1 Shunt trip and cut-off switch. Note the following:

a. For SPD AQB-A400/AQB-LF400 thermal magnetic circuit breakers with shunt trips, the vendor supplies

leads for an additional 1a, 1b aux switch where the "a" contact is used as the shunt trip cut-off switch. The

remaining "b" contact on this switch is not used in most cases; it is usually tied off when the circuit breaker is

installed in the switchboard. As an example, suppose an SPD AQB-A400 with a 1a, 1b aux switch and shunt trip is

needed. The user will see the following leads exiting the circuit breaker:

3 leads for the 1a, 1b switch for customer use

3 leads for the additional 1a, 1b aux switch ("a" contact used for shunt trip cut-off switch and "b" contact tied

off and not used)

2 leads for the shunt trip