Module powering rules:
- The leading EMA-4/4 or EMA-4/16 device must be powered by an external power supply or by a special PoE power injector.
- Do not connect the leading Sensophone EMA-4/4 or EMA-4/16 device to an external Ethernet port with PoE (Power-over-Ethernet) enabled!
- Power voltage UIN for any EMA-4/4 or EMA-4/16 device should be + 12 … + 48 VDC.
No EMA-4/4 or EMA-4/16 device with UIN less than +15 VDC can power other driven EMA-4/4 or EMA-4/16 device connected to its Expander Port .
- Power current across patch cables between EMA-4/4 and/or EMA-4/16 devices (IExpander_Port) should not be more than 750 mA.
Power current depends from actual power voltage UIN as: IEMA-4/4 = 217-2.79*UIN + IExpander_Port [mA], or IEMA-4/16 = 695-9.37*UIN + Iall_three_Expander_Ports [mA].
Power voltage difference (loss) between External Power connector and Expander Port: 1 V, between Upstream Port and Expander Port : 2 V (if enabled).
Power voltage difference (loss) on the patch cables depends from length and resistance. Resistance depends from the cable type and can be R=3 … 14.5 Ohm/100m.
- “Midway” EMA-4/4 or EMA-4/16 device can be powered by an external power supply if the power output from the upper EMA-4/4 or EMA-4/16 device is disabled.