Omega DPS3100 - Manual (Page 21)

Page 20
RATE
DPS3000 series tracks the rate of process change/minute for each channel. This rate
is displayed by first pushing the CH. SEL key to select the channel whose rate is
desired. Once the channel has been selected, push rate key. The display will
briefly read 'cx-rate' (x=channel #), and then the monitored rate for that channel.
LIMITS
DPS3000 series units support limit alarms on all the channels. These limits can be programmed over the entire range of
selected thermocouple or scale. Thus, not only can these units be used as monitors but they can also provide control
capability on each channel. Limit values are programmed during CH Setup. Also programmed during CH Setup is the
dead-band (hysteresis) value. This keeps the relays from chattering when the process is hovering just around the limit.
OUTPUTS
DPS3000 Series units can be ordered with either open collector outputs or electro-mechanical relays. Check model
number printed on the unit.
Open Collector Option
Whenever a limit is reached an open collector output provides a 5 Vdc signal at 50ma. on the output connector, eg.. Limit
#4 provides its 5 volt output signal between pins 7 & 8 of the card edge.
Figure 1. Open Collector Hookup Example
Electro-Mechanical Relay Option
These relays are programmed during CH Setup to operate as either Normally Open (NO) or Normally Closed (NC). The
default setting is Normally Open. Each of these limit relays provides a switched output whenever a limit is reached. The
maximum rating for a 120Vac unit is 120Vac @ 0.5 amp or 28 Vdc @ 1.0 amp. A 240Vac unit is rated at 240Vac @ 0.25
amp. or 28Vdc @ 1.0 amp.
Figure 2. Electro-mechanical Relays Hookup Example
8
7
LOAD
+ OUTPUT
- OUTPUT
Instrument
Solid Sate Relay
LED, Buzzer, ETC.
Switched Output
Limit # 4
Limit # 3
Limit # 2
Limit # 1
LIMIT RELAYS
Instrument
7
8
5
6
3
4
1
2
120 VAC @ 0.5 AMPS
120 VAC @ 0.5 AMPS
120 VAC @ 0.5 AMPS
120 VAC @ 0.5 AMPS
Switched Output
Switched Output
Switched Output
PLUG-IN CONNECTOR
+5VDC