Please take a look at Figure 3-4: "ER-8/16 Configurations with Multifunction DAQ Devices" which is located in the ER-8/16 User Manual which is linked below. In this figure you will find that to cable an E-Series device, such as the DAQCard-6024E, to an ER-8 you will first cable the board to an SC-2050 which will then be cabled to the ER-8 module.
ER-8/16 User Manual
http://digital.ni.com/manuals.nsf/websearch/0CC0C559A9660A9D8625665E00635884?OpenDocument&node=1731_US
SC-2050 Cable Adapter for E Series Devices
http://sine.ni.com/apps/we/nioc.vp?cid=3183〈=US
In this configuration your DAQCard-6024E will drive the ER-8 module.
Regards,
Justin Britten
Applications Engineer
National Instruments